16 results about "Harmonic impedance" patented technology

The embodiment of the application provides a power amplifier circuit, a radio frequency front end module and a communication device, relates to the technical field of electronics, and is used for improving the saturation power and saturation efficiency of the power amplifier circuit. The power amplifier circuit adopts an impedance matching network architecture of series connection of a capacitor and an inductor in at least one branch (which can be a main power amplifier branch or a peak power amplifier branch). Under the architecture, the fundamental wave impedance and the harmonic impedance of the branch are both adjusted by the series connection capacitor and inductor network. However, since the capacitance of the capacitor and / or the inductance of the inductor can be changed, the fundamental wave impedance is fixed, and the second harmonic impedance is changed. That is, when the second harmonic impedance is adjusted in a wideband range, the fundamental wave impedance can not be affected. Based on this, by reasonably selecting the capacitance of the capacitor or the inductance of the inductor, the fundamental wave impedance and the second harmonic impedance in the branch can meet the requirements respectively, so that the power amplifier circuit has relatively optimal saturation power and saturation efficiency.

This invention discloses a power system equivalent harmonic impedance identification strategy based on physical consistency constraints, comprising the following steps: First, voltage and current data at the common coupling point in the power system are collected, frequency domain analysis is performed on the data to obtain harmonic components, and the harmonic components are normalized and feature-processed to form a feature dataset for model training; then, a multilayer feedforward neural network (MLP) data-driven module and a physical information neural network (PINN) physical constraint module are designed, and a self-attention temporal convolution feature module is fused to construct a multilayer feedforward-attention physical information neural network (MLP-APINN) model; finally, the model is trained using a first-order gradient parameter iteration method, and the model parameters are updated using a learning rate adjustment strategy to obtain the identification result of the system-side equivalent harmonic impedance; this invention improves the stability and generalization performance of harmonic impedance identification by introducing physical consistency constraints, and is applicable to harmonic impedance identification at the common coupling point in the power system.

The application discloses an interface reaction kinetics parameter analysis method based on electrochemical impedance spectroscopy, and relates to the technical fields of electrochemical testing and data processing, and comprises the following steps: applying an alternating current signal with gradually increased amplitude to a to-be-tested interface, and extracting a fundamental frequency impedance vector and a harmonic impedance vector; performing anti-convolution calculation on the fundamental frequency impedance vector and the harmonic impedance vector respectively by using preset standard penalty weights, obtaining a fundamental frequency relaxation vector and a harmonic relaxation vector, and dividing the amplitudes of the two vectors by a node to obtain a response ratio; identifying an aliasing peak interval with an information entropy greater than an entropy value determination threshold in the fundamental frequency relaxation vector, wherein the aliasing peak interval contains an aliasing peak, and the aliasing peak only overlaps with an extreme value point of the response ratio; and the method has the beneficial effect that the evaluation error caused by improper selection of a human prior model is reduced, and the reliability of interface kinetics parameter analysis is ensured.

The present application relates to the technical field of electric variable detection, and in particular to a kind of active distribution network harmonic source positioning method and system, method includes: determining the probability characteristics of each substation in the current monitoring time period, in combination with the harmonic impedance attenuation characteristics of each substation, total harmonic current increment of substation is divided, the dynamic responsibility current distribution of each substation is obtained, in combination with historical harmonic responsibility index stock, obtain the latest harmonic responsibility index stock of each substation in the current monitoring time period, thereby screening substation, and the latest harmonic responsibility index stock and fundamental current effective value of target substation are fused, to obtain the electric-thermal comprehensive characteristic load of target substation, and then obtain the transformer insulation deterioration risk index of target substation, finally by transformer insulation deterioration risk index, the accurate positioning of distribution network harmonic source is realized, and the operation safety and operation efficiency of distribution network are significantly improved.

The application provides a distributed power balancing and voltage regulating method for a current control type converter cluster. The method belongs to the field of micro-grid control, and is based on reactive voltage droop and voltage amplitude control to generate a reference current amplitude of the parallel converter, so that each parallel converter outputs the same current amplitude; meanwhile, the phase of the current vector is determined by four-quadrant power factor control, so as to ensure that the output currents among the parallel converters are in the same phase state, and the load side currents are effectively superimposed and the maximum load current is obtained. In view of the harmonic problem caused by the access of a nonlinear load, the application further adopts harmonic virtual impedance control at a fundamental frequency and selected harmonic frequencies, and combines with the multi-resonance controller adjustment of the current loop to effectively reduce the amplitude of the equivalent harmonic impedance of the DG unit, so that the harmonic circulating current among the DGs is minimized, and the power quality at the point of common coupling (PCC) is improved.

The application discloses a wireless power transmission system topology and a parameter design method thereof. The topology comprises an inverter circuit, a primary side compensation network, a primary side induction coil, a secondary side compensation network and a rectifier circuit. The resonant inductance in the primary side compensation network is connected in series with a first capacitive element to form a first resonant branch, and is connected in parallel with a second capacitive element and a second resonant branch comprising the primary side induction coil through a parallel node. The harmonic impedance characteristics are reconfigured, and the attenuation degree of high-order harmonics is adjustable through the capacitance ratio. The parameters satisfy the zero phase angle condition to realize constant voltage output, and satisfy the soft switching condition to cooperatively optimize harmonic suppression and zero voltage switching. The application actively suppresses high-order harmonics while maintaining constant frequency and constant voltage output, reduces light load loss, realizes full range soft switching, and is suitable for wireless charging scenes such as electric vehicles and industrial automatic guided vehicles.

The present application relates to the field of wind power converter compensation control, and provides a wind power converter grid-connected point harmonic adaptive compensation control method and system, which realizes zero-intrusion online identification of grid harmonic impedance by coordinate transformation and target harmonic component extraction on grid-connected point voltage and current signals; based on this, the identified grid harmonic impedance estimation value is used to adaptively calculate the proportional and integral gains of harmonic compensation in combination with the preset system target dynamic performance; finally, the adaptive gains are used to generate and superimpose harmonic compensation instructions to adjust the output voltage of the converter. In this way, the wind power converter can dynamically adjust its parameters when facing complex and variable grid impedance, thereby effectively avoiding the problem of compensation effect deterioration or even resonance caused by grid impedance changes, greatly improving the robustness and stability of harmonic suppression, and ensuring the power quality of the wind power grid-connected system under various operating conditions.

The present application relates to the technical field of power quality treatment, and particularly relates to a harmonic source positioning method and device, electronic equipment and storage medium. The method comprises the following steps: firstly, obtaining current waveform data sets; then, according to target harmonics, performing harmonic current analysis on a plurality of feeder current waveform data queues in the current waveform data sets to obtain a plurality of harmonic current vectors and construct the harmonic current vectors into harmonic current data sets; then, according to a topology structure formed by a main power supply, a plurality of load feeders and a plurality of power supply feeders and the harmonic current data sets, constructing a harmonic voltage equation set expressing the relationship among harmonic currents, bus section harmonic impedances and harmonic voltage differences between feeders; finally, determining a harmonic source according to a plurality of bus section harmonic impedances and the plurality of harmonic current data sets. The present application is based on harmonic currents and topology structures, analyzes the harmonic current trend and harmonic impedance in the power grid, and finally determines the feeder with the largest harmonic contribution degree, so that the harmonic source positioning is more accurate.

The application discloses a 6-18GHz power amplifier with active matching combined with passive matching, which comprises a passive input matching network, an active input matching network, a passive inter-stage matching network, an active inter-stage matching network, a passive output matching network, an active output matching network, a first transistor and a second transistor; the impedance position of the first transistor and the second transistor is accurately controlled in a manner that active matching is combined with passive matching. The implementation method of the application firstly preliminarily matches the transistor impedance position through a passive matching circuit, reduces the matching difficulty, and then corrects the fundamental wave impedance position and the harmonic impedance position through active matching on the basis, so that the impedance position is accurately controlled. The application solves the problem that the transistor impedance in the traditional ultra-wideband power amplifier cannot be ideally matched at all frequency points, and finally improves the overall efficiency of the 6-18GHz power amplifier.

The application relates to a wideband high-efficiency rectifier circuit based on a GaN HEMT, which comprises an input matching network, a harmonic suppression network, a direct-current output circuit, a second harmonic suppression network, a current stabilizing circuit, a radio frequency junction gate field effect transistor, a gate matching network and a gate bias circuit; the input matching network is used for direct-current isolation processing of received signals; the harmonic suppression network is used for suppressing second and third harmonics, adjusting fundamental wave impedance and expanding the distribution interval of each harmonic impedance to realize wideband characteristics; the direct-current output circuit is used for converting input alternating-current power into direct-current power for output; the second harmonic suppression network is used for suppressing the second harmonic of the gate of the radio frequency junction gate field effect transistor; the current stabilizing circuit is used for preventing the whole circuit from oscillating; the gate matching network is used for impedance matching between the second harmonic suppression network and the ground end; and the gate bias circuit is used for providing direct-current bias voltage for the gate of the radio frequency junction gate field effect transistor.

The application discloses a high-efficiency microwave power amplifier design method based on limited harmonic control, which aims at improving the efficiency of the microwave power amplifier by reducing the useless energy of the transistor and increasing the output power of the transistor, and solves the problem of low efficiency of the high-power amplifier.The application takes the power amplifier power distribution mechanism under the limited harmonic condition as the starting point, increases a small amount of second harmonic output energy to reduce more transistor dissipation energy, and makes the voltage waveform fundamental wave and second harmonic out of phase to obtain the maximum fundamental wave component.Meanwhile, the application provides a current waveform which can be used with the above-mentioned voltage waveform, so as to ensure that the fundamental wave / harmonic impedance of the output port is always non-negative, and solves the problem of low efficiency of the high-power amplifier when realizing higher output power.

The application discloses a kind of power system harmonic impedance frequency characteristic measurement method, device, equipment and medium, for solving the technical problems of low efficiency, processing delay and simulation real-time insufficient of harmonic impedance measurement.It includes: when receiving the sweep starting instruction sent by user, generate the disturbance current signal of multiple frequency points using preset sweep parameter;The disturbance current signal is injected into the injection node of the electromagnetic transient simulation model of power system, and with preset simulation time step as sampling interval, the voltage time domain data of injection node and the current time domain data formed by disturbance current signal are continuously collected;The voltage time domain data is subjected to fast fourier transform, and the voltage complex spectrum is obtained, and the current time domain data is subjected to fast fourier transform, and the current complex spectrum is obtained;The equivalent impedance of multiple frequency points is calculated using voltage complex spectrum and current complex spectrum;Harmonic impedance frequency characteristic curve is generated using the equivalent impedance of multiple frequency points.

The application provides an alternating current-direct current complementary resonance detection method and device, a storage medium and computer equipment. The method comprises the following steps: obtaining a system stability parameter model of a direct current power transmission system when a complementary resonance condition is met; the complementary resonance condition is that the frequency of an alternating current side is a first frequency and the frequency of a direct current side is a second frequency; obtaining alternating current harmonic impedance and alternating current impedance phase angles of the alternating current side at the first frequency; obtaining direct current harmonic impedance and direct current impedance phase angles of the direct current side at the second frequency; respectively calculating a trigger angle curve and a commutation overlap angle curve of a converter working in a target power interval of the direct current side; using the system stability parameter model, calculating system stability parameters at different target powers; if the system stability parameters are less than 0, determining that there is a complementary resonance risk at the target power corresponding to the system stability parameters less than 0. The application can analyze the complementary harmonic risk in advance, which is beneficial to improving the system stability.

This application relates to an impedance determination method, apparatus, broadband power amplifier, storage medium, and program product for a broadband power amplifier. The impedance determination method determines the optimal impedance of the power amplifier tube's package surface based on the performance parameters of the power amplifier tube and the reactance parameters of the broadband power amplifier. It then applies a pull-type processing method to the optimal matching impedance of the power amplifier tube's package surface. This impedance determination method achieves pull-type processing based on the optimal impedance of the power amplifier tube's package surface, obtaining the optimal fundamental impedance at the input end, the optimal second harmonic impedance at the output end, the optimal third harmonic impedance at the output end, and the optimal fundamental impedance at the output end. This allows the broadband power amplifier to maintain broadband operation while simultaneously achieving high efficiency, meeting the wide bandwidth and high efficiency requirements of modern wireless communication technologies.

This invention proposes a harmonic impedance identification method based on transient energy triggering and covariance correction, belonging to the technical field of harmonic impedance identification in AC distribution networks. The method includes: establishing a linear regression model of harmonic impedance and constructing a limit convergence model based on broadband voltage and current signals from the transmission line's point of common coupling; constructing a local transient energy variation index based on the broadband voltage signal, establishing a comparison relationship between this index and an adaptive threshold, and generating a binary state trigger signal; responding to this signal, establishing a frequency-band differentiated dynamic covariance adaptive correction Q matrix, superimposing this Q matrix onto the prior error covariance time update equation, modifying the recursive relationship of the covariance matrix, and embedding a piecewise robust weight function into the Kalman gain equation to perform harmonic impedance parameter updates; performing matrix trace and gain limit operations on the updated parameters, and outputting the broadband harmonic impedance identification result. This invention achieves rapid tracking of impedance abrupt changes and online identification of broadband harmonic impedance.

This invention discloses a harmonic responsibility allocation method considering the asynchronicity of monitoring data and harmonic impedance changes. The method includes: preprocessing the harmonic monitoring data to obtain preprocessed harmonic monitoring data; aligning the asynchronous feeder harmonic current data and bus harmonic voltage data in the preprocessed harmonic monitoring data to obtain aligned harmonic monitoring data; dividing the aligned harmonic monitoring data into data clusters for different scenarios; and then using correlation analysis to allocate harmonic responsibility based on the data in each cluster. This invention avoids the inaccuracy of calculation results caused by directly using raw data for harmonic responsibility allocation; based on the DTW algorithm matching, the ShapeDTW algorithm is used to incorporate the local shape information around the sequence points into the dynamic programming matching process to achieve data matching and alignment; and considering the impact of system harmonic impedance changes on harmonic responsibility allocation, thus avoiding doubts about the rationality and applicability of the harmonic responsibility allocation results.