901 results about "Output impedance" patented technology

The invention relates to the technical field of power system stability control, in particular to a broadband oscillation suppression method and system for an offshore wind power flexible direct current grid-connected system and a medium, and the method comprises the steps: sequentially injecting positive and negative sequence perturbation sine harmonic signals at a grid-connected point of a wind turbine generator, constructing a multi-input multi-output impedance matrix, reducing the order of the multi-input and multi-output impedance matrix into single-input and single-output equivalent positive sequence impedance; the stability margin of the offshore wind power flexible direct current grid-connected system is obtained based on equivalent positive sequence impedance quantification; when the stability margin is lower than a preset margin threshold value, reconstructing the fan grid-side converter into a matrix control structure by cascading a weighting coefficient matrix between the inner and outer ring control loops of the fan grid-side converter; and iteratively optimizing the matrix type control structure based on impedance sensitivity, and synchronously connecting a low-pass filter in series in a voltage and current feedback channel to carry out impedance remodeling so as to finish broadband oscillation risk suppression. According to the invention, broadband oscillation suppression of the offshore wind power flexible direct current grid-connected system is realized through impedance modeling and a matrix type control strategy.

The invention relates to the technical field of energy storage power station combined operation and maintenance management, and provides a virtual power plant-oriented energy storage power station combined operation and maintenance management system, which comprises a dynamic sensing module for acquiring battery cluster temperature difference distribution, power converter switch transient characteristics and grid-connected point harmonic spectrum data of an energy storage power station in real time through a multi-dimensional sensor network; the collaborative decision-making module is used for dynamically generating a cross-station power interaction constraint rule based on the virtual power plant topological structure; the impedance reconstruction module adjusts the equivalent output impedance of the energy storage converter in real time according to the impedance characteristics of the power grid; the state balancing module is used for realizing charge state dynamic balance and power margin collaborative distribution among the multiple energy storage power stations; and the secure communication module is used for ensuring secure transmission of control instructions among the modules by adopting a layered encryption protocol. The operation stability, the power distribution flexibility and the equipment safety of the virtual power plant can be improved, and the service life of the energy storage equipment is prolonged.

The invention relates to a weak current cable fault positioning method and system, and the method comprises the steps: preliminarily locking a fault region through monitoring the axial stress change in real time, injecting a low-frequency pulse signal in a target section, analyzing the reflection waveform characteristics, and extracting the waveform distortion characteristics in a reflection signal; dynamically adjusting the output impedance based on the amplitude attenuation and time delay relationship, and if the dynamically adjusted output impedance cannot enable the output impedance of the injected low-frequency pulse signal to be synchronous with the impedance change trend of the cable, marking as an impedance mismatch point; after an impedance mismatch point is identified, other interferences are eliminated through multi-band signal attenuation difference analysis, and the position of a fault point is determined; the system is used for implementing the method. According to the method and system, stress monitoring and electric signal detection are combined, the detection range is remarkably shortened, the positioning precision and the detection accuracy are improved, and the method and system are suitable for weak current cable fault diagnosis in a complex environment.

The invention discloses a power grid cross-correlation harmonic suppression method, device and equipment and a storage medium, and the method comprises the steps: carrying out the wavelet packet decomposition of a subnet electric signal, and obtaining the harmonic component of a subnet at each frequency band; calculating the harmonic phase difference between the subnets according to the cross-correlation function between the harmonic components of the subnets and the topological impedance matrix, and calculating the total harmonic distortion rate according to the harmonic components of the subnets in the frequency bands; constructing a harmonic transfer equation according to the harmonic phase difference between the subnets and the equivalent output impedance of the inverter so as to calculate the harmonic responsibility proportion of the subnets; solving the double-layer game model based on the total harmonic distortion rate, the reference value of the total harmonic distortion rate and the harmonic responsibility proportion of the subnet, and obtaining the output of the governance equipment; and inputting the output of the treatment equipment into the fuzzy controller to obtain the impedance adjusting quantity of the subnet, and adjusting the virtual impedance according to the impedance adjusting quantity to update the harmonic backflow path. According to the invention, harmonic suppression among multiple subgrids during high-permeability distributed grid connection is realized, and the operation stability of the power grid is improved.

Aiming at the stability problem caused by harmonic resonance of multiple parallel photovoltaic inverters, the invention provides a parallel inverter micro-grid-oriented adaptive virtual impedance remodeling harmonic resonance suppression method, which comprises a virtual impedance remodeling unit of a grid-connected inverter, a parameter adaptive adjustment unit and a power grid impedance online detection unit. The virtual impedance remodeling unit can improve the output impedance characteristic of the grid-connected inverter and inject a certain damping component into the micro-grid; and the parameter adaptive adjustment unit adaptively adjusts control parameters in the virtual impedance remodeling unit and the current adjustment controller according to the impedance parameters of the power grid so as to maintain the stability of a system control loop. The power grid impedance online detection unit provides power grid equivalent impedance as the input of the parameter adaptive adjustment unit. The three units work cooperatively to form a self-adaptive virtual impedance remodeling multi-inverter micro-grid harmonic resonance suppression strategy, so that the characteristics of a current loop are improved, the inverters can be kept stable under various grid impedance conditions, and the reliability of a multi-inverter micro-grid system is improved.

The invention discloses a method for measuring the impedance of a grid-connected inverter, which relates to the technical field of impedance measurement of the grid-connected inverter and is characterized in that impedance types and measurement accuracy needing to be measured are determined, the impedance types comprise output impedance and ground insulation impedance, and according to the measurement method and equipment requirements, a data acquisition module is used for setting parameters for acquiring measurement data, the parameters comprise a frequency range, a current amplitude value and a voltage amplitude value, the data processing and analysis module processes and analyzes measured data, calculates an impedance value, compares a calculation result with an expected value and a previous measured value for verification, and in the measurement process, the control and safety module controls starting, stopping and parameter setting of measurement equipment, so that the measurement accuracy is improved. And the working state of the inverter and the safety condition in the measurement process are monitored in real time, and the measurement process, the measurement result and the analysis are written into a measurement report to be uploaded to a system terminal, so that the accuracy and the reliability of impedance measurement of the grid-connected inverter are improved.

The invention relates to the technical field of power electronic control, and discloses a voltage and current stabilization and surge suppression cooperative control method for power equipment, and the method comprises the following steps: dynamically segmenting an output current frequency band, and remodeling the output impedance characteristics of a system; predicting and controlling a hierarchical optimization control target based on a multi-time scale model; dynamically switching an energy feedback path; identifying aging parameters of the device on line and adaptively adjusting a control strategy; global stability verification and fault-tolerant protection: verifying the stability of the control system based on the Lyapunov stability theory, and triggering a protection mechanism when the magnetic flux is saturated or the aging of the device exceeds the limit. By means of dynamic impedance frequency domain segmentation, the impedance characteristic of the system is divided into a low-frequency voltage stabilization area and a high-frequency surge suppression area according to frequency bands, the contradiction that in a traditional method, it is difficult to consider steady-state precision and transient surge suppression at the same time due to the single impedance characteristic is solved, and collaborative optimization of voltage stabilization control and surge energy blocking is achieved.

Certain aspects of the present disclosure are directed to a radio frequency digital-to-analog converter (RFDAC). The RFDAC generally includes a plurality of digital-to-analog (DAC) unit cells. At least one DAC unit cell is capable of being configured in an active state or in a sleep state. For the at least one DAC unit cell, an output impedance of the DAC unit cell in the active state is equal to an output impedance of the DAC unit cell in the sleep state.

The invention provides a strong series compensation grid-connected stability regulation and control method of a grid-forming type energy storage converter and a related device, and belongs to the technical field of grid connection of a power grid. According to the method, a three-phase grid-connected inverter complete sequence impedance model controlled by the virtual synchronous generator is established by using a harmonic linearization method, and reasons for causing subsynchronous oscillation by using a double-closed-loop control strategy are analyzed. In order to improve the grid-connected stability of a strong series compensation power grid of a grid-forming type energy storage converter, a PI-LADRC control strategy is provided, a sequence impedance model under the control mode is established, and grid-connected stability margin information under the PI-LADRC control strategy is obtained by comparing output impedance characteristics of a grid-connected inverter under a double closed-loop control mode and a PI-LADRC control mode. According to the invention, the PI-LADRC control strategy is adopted, so that the grid-connected stability can be effectively regulated and controlled.

The invention discloses a column type distribution transformer winding abnormity detection system and detection method. The detection system comprises a frequency response detection instrument, a signal coupling assembly, an impedance matching module and a data processing module. The frequency response detection instrument is used for outputting a frequency sweep excitation signal and collecting a winding response signal; the signal coupling assembly is used for isolating power frequency voltage and filtering low-frequency interference; the impedance matching module is used for adjusting output impedance and input impedance to realize matching with electrical characteristics of different windings; and the data processing module is used for constructing an equivalent detection loop model, completing frequency response simulation calculation and carrying out frequency domain analysis and anomaly identification on an actually measured response curve. According to the invention, electrified state diagnosis of distribution transformer winding structure abnormity (such as deformation and loosening) can be realized.

Various RF plasma systems are disclosed that do not require a matching network. In some embodiments, the RF plasma system includes an energy storage capacitor; a switching circuit coupled with the energy storage capacitor, the switching circuit producing a plurality of pulses with a pulse amplitude and a pulse frequency, the pulse amplitude being greater than 100 volts; a resonant circuit coupled with the switching circuit. In some embodiments, the resonant circuit includes: a transformer having a primary side and a secondary side; and at least one of a capacitor, an inductor, and a resistor. In some embodiments, the resonant circuit having a resonant frequency substantially equal to the pulse frequency, and the resonant circuit increases the pulse amplitude to a voltage greater than 2 kV.

The invention discloses a wind power system composite oscillation suppression strategy and system based on a static synchronous compensator, and the strategy comprises the steps: firstly constructing a sequence impedance model of a GFM-STATCOM and an equivalent wind turbine generator (EWTG) based on a wind power output system containing the GFM-STATCOM; combining the impedance contribution degree beta, analyzing the interaction between the two, and determining the oscillation risk dominant factor of the sub / super-synchronous frequency band; and finally, performing frequency-band suppression: aiming at the problem of negative damping dominance of the subsynchronous frequency band GFM-STATCOM, adopting a control parameter optimization strategy based on parameter sensitivity, and reducing a reactive loop integral coefficient by increasing virtual resistance so as to reduce a negative damping range. In order to solve the problem of negative damping leading of a super-synchronous frequency band EWTG, a virtual admittance control strategy based on voltage feedforward is adopted to reduce the output impedance amplitude of a GFM-STATCOM, the leading position of positive damping of the GFM-STATCOM is enhanced, and then the negative damping of the system is eliminated. According to the invention, precise suppression of composite oscillation is realized, and the stability of a wind power sending system under a weak power grid is improved.

The invention provides a grid-connected inverter impedance detection method based on an L-shaped filter, and belongs to the technical field of grid-connected inverter impedance detection. A multi-frequency-point disturbance signal is injected into a preset grid-connected inverter working point, time domain data of inverter side current and common coupling point voltage are collected, fast Fourier transform analysis is carried out on the collected data, amplitude and phase information corresponding to each injection frequency point is extracted, and a frequency domain feature vector matrix is established; and establishing a frequency compensation matrix model to compensate and correct high-frequency band measurement data based on a frequency characteristic attenuation vector, calculating to obtain optimal estimated values of power grid impedance and grid-connected inverter output impedance, performing error analysis and precision verification on an impedance detection result, and outputting a verified impedance parameter value. The technical problem of insufficient power grid impedance detection precision caused by high-frequency band attenuation of the L-shaped filter is solved.

The invention discloses an active damping control system for improving the output impedance of a current source type inverter, which comprises a current loop control loop, an active damping branch and an improved phase-locked loop, and is characterized in that the difference value of reference current and feedback network access current passes through a current controller to form the current loop control loop; the voltage of the grid-side inductor is fed back to the output of the current loop through the virtual resistor link to form a damping branch, and the voltage of the common coupling point enters the traditional phase-locked loop link through the low-pass filter and forms an improved phase-locked loop through phase compensation. The optimal feedback coefficient of the damping branch is designed according to the optimal damping ratio, the low-pass filter parameters are designed according to the phase at the maximum resonant frequency, the reasonable proportional gain link is designed according to the improvement of the output impedance amplitude, the resonance of the current source type inverter can be effectively inhibited, the output impedance of the inverter is increased, and the output impedance of the inverter is improved. And the quality of the network access current of the current source type inverter and the stability margin of the current source type inverter in a weak power grid are improved, and the stability of the system is improved.

The invention discloses a double-fed wind power plant series compensation sending-out system subsynchronous oscillation suppression method for achieving negative damping full compensation design, and belongs to the technical field of impedance characteristic optimization, and the method comprises the steps: simplifying a double-fed wind power plant series compensation sending-out system, and obtaining the equivalent output impedance and series compensation line impedance of a double-fed fan; in the simplified system, the equivalent output impedance of the doubly-fed fan is further simplified, a negative damping factor index is introduced according to the simplified equivalent output impedance of the doubly-fed fan and series compensation line impedance, and whether subsynchronous oscillation exists in the system or not is judged; a positive feedback control branch for realizing negative damping full compensation is added in a simplified system, and positive feedback gain and a negative damping item are designed to realize positive and negative cancellation; and carrying out adaptive adjustment on the positive feedback gain under different working conditions. According to the invention, oscillation risk suppression can be realized, the drift of the oscillation mode under different working conditions can be suppressed, the subsynchronous frequency band impedance characteristic of the doubly-fed fan is effectively optimized, and the operation stability of the system is improved.

According to the novel weak node detection and instability index establishment method and system for the electric power system, the linkage relation between oscillation characteristic samples is mapped into different value ranges of the equivalent impedance angle of an inverter, and the actual value of the equivalent impedance angle of the inverter is calculated according to the relation between the actual value of the equivalent impedance angle of the inverter and the different value ranges, obtained through mapping, of the equivalent impedance angle of the inverter. Forming a novel power system stability criterion; taking the nodes of which the load flow entropy weakness indexes are not less than a set threshold value as weak nodes; under the constraint conditions of the power angle, the voltage, the frequency and the impedance angle, establishing a multi-dimensional stability margin space by using the coupling relationship among the power angle stability margin, the voltage stability margin, the frequency stability margin and the impedance angle stability margin; constructing a stability margin index of the weak node by using the equivalent impedance angle actual value of the inverter and the equivalent output impedance amplitude of the inverter; and when the stability margin index of the weak node exceeds the multi-dimensional stability margin space, determining that the novel power system is unstable.

The invention provides a fully differential operational amplifier circuit and an operational amplifier. The fully differential operational amplifier circuit comprises an input stage circuit, a gain stage circuit and a common-mode feedback circuit, the input stage circuit is used for processing a differential input voltage signal, converting the differential input voltage signal into a differential current signal and transmitting the differential current signal to the gain stage circuit; the gain stage circuit is used for performing gain processing on the differential current signal and outputting a target differential voltage signal; the common-mode feedback circuit is used for detecting the common-mode voltage of the target differential voltage signal, generating a common-mode feedback signal and transmitting the common-mode feedback signal to the gain-stage circuit to stabilize the common-mode voltage; wherein the gain stage circuit comprises a gain enhancement circuit, and the gain enhancement circuit is used for increasing the output impedance of the gain stage circuit. According to the chopping operational amplifier, the input stage circuit, the gain stage circuit, the common mode feedback circuit and the gain enhancement circuit are combined, so that the precision and the sensitivity of the chopping operational amplifier are improved.

The embodiment of the invention provides a high-sensitivity vibration measurement and analysis instrument. In the embodiment of the invention, the signal buffering and driving sub-module in the signal conditioning module effectively isolates the sensor from a subsequent circuit by providing high input impedance and low output impedance, the load effect of a signal source is prevented, and the integrity and stability of the signal in the transmission process are ensured. Moreover, the driver part enhances the driving capability of the signal, so that the signal can overcome the impedance of a transmission line, and the attenuation of the signal in long-distance transmission is reduced, thereby guaranteeing the quality of the signal, and enabling the adaptive gain controller sub-module to automatically adjust the gain according to the intensity of the input signal. By means of the innovative design, the system can keep the best sensitivity when facing vibration signals of different amplitudes, signal saturation is avoided, it is guaranteed that weak vibration or strong vibration can be accurately measured, and the data accuracy in the digital signal processing stage is guaranteed.

The invention relates to the technical field of self-synchronizing voltage source control, and discloses a balance current controlled self-synchronizing voltage source control method and system. The method comprises the following steps: acquiring and preprocessing operation data of a grid-connected inverter to obtain active / reactive components of voltage and current of a filter element; generating a three-phase terminal voltage instruction of the self-synchronizing voltage source based on the components, and determining a current instruction signal in combination with the grid-connected voltage; a three-phase modulation signal is generated through adjustment of a PIR controller and coordinate inverse transformation, then a filter inductance value is calculated according to the ripple characteristic of the modulation signal and a switching period, a filter capacitance value is determined by combining resonant frequency, and finally accurate control of the self-synchronizing voltage source is realized according to a filter parameter. By dynamically calculating the matching parameters of the filter inductance and the filter capacitance, the active regulation and control capability of the output impedance characteristic of the inverter is enhanced, and the resonance risk during the impedance change of the power grid is effectively inhibited. The technical problem that the stability is limited due to insufficient impedance regulation and control in the prior art is solved.

The invention relates to the technical field of circuit board conductivity detection, and discloses a circuit board conductivity detection method and system based on deep learning, and the method comprises the steps: obtaining high-resolution image data and circuit design parameters of a to-be-detected circuit board, and generating a circuit board feature data set; calculating theoretical impedance distribution of each area of the circuit board by using a physical constraint neural network based on the circuit board feature data set, and outputting an impedance prediction parameter set; inputting the impedance prediction parameter set and the circuit symbol rule into a neural symbol inference device to generate a conductance fault diagnosis result; and obtaining diagnosis results of a plurality of detection sites, executing cross-site diagnosis fusion, and outputting a unified circuit board conductivity detection report. The method overcomes the limitation that a traditional visual detection method cannot identify electrical characteristic defects, and solves the detection problem of hidden faults such as discontinuous impedance of the high-frequency circuit board.

The invention discloses a differential closed-loop negative feedback amplification circuit based on JFET geminate transistors, a low-noise amplifier is used for measuring weak voltage signals, discrete JFET field-effect transistors are used for forming an input stage of the low-noise amplifier, noise interference is reduced, meanwhile, extremely high input impedance can be provided by using the characteristic that the grid current of the JFET field-effect transistors is basically zero, and the differential closed-loop negative feedback amplification circuit based on the JFET geminate transistors is obtained. Mirror current is provided for a pair of JFET field effect transistors in the low-noise amplifier module through a current mirror of the low-noise amplifier, a closed-loop feedback structure of the low-noise amplifier can save one path of input for the JFET field effect transistors, so that the amplifying circuit can realize dual-channel input, and a dual-channel input structure can enable an accessed signal to be a differential signal, so that common-mode interference is effectively inhibited, and the reliability of the amplifying circuit is improved. Overall closed-loop negative feedback can achieve high gain stability, reduce nonlinear distortion, increase input impedance, reduce output impedance and improve the performance of the amplifier, and solves the problem of precise amplification and measurement of weak voltage signals in the aviation electromagnetic field.

The invention discloses a composite impedance remolding stability improving method based on power grid voltage feedforward, and the method comprises the steps: connecting a low-pass filter in series in a power grid voltage proportion feedforward link, maintaining the power grid voltage feedforward low-frequency harmonic suppression capability, and improving the phase margin of the output impedance of an inverter in a middle-high frequency band at the same time. And a power grid voltage feed-forward branch for eliminating the negative damping influence of the phase-locked loop is added to a public grid-connected point, so that the stability of the grid-connected inverter is improved, the phase margin of the system is greatly improved, and the grid-connected inverter can still keep higher robust stability when the impedance of the power grid is higher. The stability of the grid-connected inverter is improved when the impedance of the power grid changes in a wide range, the quality of grid-connected current is improved, and the problem that the system is faced with instability after the influence of power grid voltage feedforward and PLL is considered under a weak power grid is effectively solved.

The present application discloses a method, apparatus, device and storage medium for cross-correlated harmonic control in power grids. The method includes: performing wavelet packet decomposition on subnet electrical signals to obtain the harmonic components of the subnet in each frequency band; calculating the harmonic phase difference between subnets based on the cross-correlation function and topological impedance matrix between the harmonic components of each subnet, and calculating the total harmonic distortion rate based on the harmonic components of the subnet in each frequency band; constructing a harmonic transfer equation based on the harmonic phase difference between subnets and the equivalent output impedance of the inverter to calculate the harmonic responsibility ratio of the subnet; solving a two-layer game model based on the total harmonic distortion rate and its reference value and the harmonic responsibility ratio of the subnet to obtain the output of the control equipment; inputting the output of the control equipment into the fuzzy controller to obtain the impedance adjustment amount of the subnet, and adjusting the virtual impedance according to the impedance adjustment amount to update the harmonic return path. The present application realizes the harmonic control between multiple subnets during high-penetration distributed grid connection, thereby improving the stability of power grid operation.

The utility model relates to a power supply device and a testing machine, the power supply device comprises a main loop, a voltage loop, a current loop and a clamping circuit, in a pressurization mode, when a detection current output by the clamping circuit at the current loop is in a set current clamping range, the output impedance is high resistance; and when the detection current output by the current loop is not in a set current clamping range, the clamping circuit triggers the clamping current to carry out analog output, and the output impedance is switched to low resistance, so that the output of the main loop is equivalent to a constant current source. In the current adding mode, when the detection voltage output by the clamping circuit at the voltage loop is within a set voltage clamping range, the output impedance is high resistance; and when the detection voltage output by the voltage loop is not in a set voltage clamping range, the clamping circuit triggers the clamping voltage to perform analog output, and the output impedance is switched to low resistance, so that the output of the main loop is equivalent to a constant voltage source. The simulation regulation function is achieved, and the response speed is high.

The invention discloses a network construction converter virtual impedance and power reference cooperative adjustment method and system, and relates to the technical field of power control, a virtual synchronous generator system introduces virtual impedance to increase equivalent output impedance of an inverter, and an internal voltage reference generated by a virtual synchronous generator algorithm of the inverter is monitored in real time; monitoring the local voltage measured by the common coupling point in real time; based on the vector difference between the internal voltage reference and the local voltage, the accurate amplitude of the virtual impedance is solved in real time by combining the maximum current limit value of the power electronic device; and determining a function relationship between an active power reference value and reactive power based on the accurate amplitude of the virtual impedance, monitoring the reactive power measured at the common coupling point in real time, and adjusting the active power reference value according to the function relationship to keep a stable balance point. And virtual impedance is dynamically calculated to accurately limit current, and active power reference is adaptively adjusted according to real-time reactive response, so that maximized power grid support and safe and stable operation of the converter are realized.

An embodiment includes a controller and a driver. The controller controls to drive a semiconductor element having a first gate electrode and a second gate electrode base on a control signal. The driver outputs a first driving signal to the first gate electrode and a second driving signal to the second gate electrode. The first driving signal drives the first gate electrode at ON or OFF timing of the control signal. The second driving signal drives the second gate electrode a timing earlier than the OFF timing of the control signal. The driver switches output impedances corresponding to the switching speed of the semiconductor element.

The invention discloses a photon antenna working at 275-296 GHz, and belongs to the field of photoelectron and terahertz communication. The UTC-PD comprises two UTC-PD bodies and a passive structure. The UTC-PD body adopts a double-mesa structure, each structure leads out an electrode by electroplating a small bonding pad, a metal bump is processed on the small bonding pad, and the UTC-PD body is electrically connected with a passive structure through flip-chip bonding. The passive structure comprises an impedance matching circuit, a power combiner circuit and a vivaldi antenna; the UTC-PD body generates a signal, and a built-in electric field is introduced by using the gradient doped absorption layer; a cliff layer is arranged between the absorbing layer and the collecting layer; and then, after the signal passes through an impedance matching circuit, the output impedance is close to 50 ohms, two combined output signals are superposed to the feed end of the Vivaldi antenna through a power combiner, and finally, the two combined output signals are converted into high-frequency electromagnetic waves with the frequency band of 275-296 GHz for radiation. Electromagnetic waves within the terahertz frequency range are generated and emitted, and the technical performance of high bandwidth, high gain and low insertion loss is achieved.

The invention discloses an inverter parallel current sharing control method based on virtual reactive voltage self-adjustment, and belongs to the technical field of coordination control of parallel inverters. Compared with traditional droop control, the reactive power equalization degree can be well improved, and the reactive power equalization effect and the response speed when the load power changes are enhanced. According to the invention, the relation between the output power and the output impedance of the inverter is deeply analyzed, the characteristics of loop chain control and traditional droop control are combined, and a reactive loop chain and self-adjusting virtual reactive voltage control are introduced, so that the virtual impedance can realize self-adaptive adjustment according to circular chain type tracking of reactive power output by a parallel module; mismatch between output impedances of the parallel modules is compensated, and output reactive power balance of the parallel modules is achieved. In addition, the voltage of a common coupling point does not need to be measured, the requirement for a communication network is low, the system reliability and safety are higher, and good reference value is provided for engineering application.

The invention belongs to the technical field of power management, and particularly relates to a double-phase DC-DC topological structure with a current multiplier. The invention is characterized in that a current multiplier and a switched capacitor SC buck are embedded on the basis of the traditional multiphase buck, the inductive current and the RMS current of a buck power device are greatly reduced, the current stress is transferred to a charge pump structure of a low-voltage and low-FoM-value device, and the voltage stress is retained in a high-voltage device of the buck. And high conversion efficiency is realized through a strategy that the charge pump and the buck share current and voltage stress respectively. Meanwhile, due to the fact that the switched capacitor has extremely low output impedance, and the circuit is compatible with a loop control strategy of a traditional multi-phase buck, the transient response speed is also remarkably improved. The idea of the invention can be linearly expanded from typical two-phase buck to N-phase buck, so that the topological structure of the invention has universality.

Various RF plasma systems are disclosed that do not require a matching network. In some embodiments, the RF plasma system includes an energy storage capacitor; a switching circuit coupled with the energy storage capacitor, the switching circuit producing a plurality of pulses with a pulse amplitude and a pulse frequency, the pulse amplitude being greater than 100 volts; a resonant circuit coupled with the switching circuit. In some embodiments, the resonant circuit includes: a transformer having a primary side and a secondary side; and at least one of a capacitor, an inductor, and a resistor. In some embodiments, the resonant circuit having a resonant frequency substantially equal to the pulse frequency, and the resonant circuit increases the pulse amplitude to a voltage greater than 2 kV.