92 results about "Small-signal model" patented technology

The invention discloses a single-loop droop control method and system for a wind generating set, and the method comprises the following steps: constructing a doubly-fed fan-power converter-power grid three-module coupling model, and completing the dynamic adaptation of the characteristics of a doubly-fed fan of a single-loop droop control architecture without inner-loop current control; based on the input signal-model collaborative integration body and the adaptive architecture, MIMO-GBC is adopted to analyze a phase margin and a resonance peak value of an open-loop transfer function matrix eigenvalue of a dynamic small signal model, and double risks are identified in a full slip rate interval; aiming at the resonance risk, a current induction type virtual impedance strategy is adopted; aiming at insufficient phase margin, adopting a transient phase calibration strategy; and according to the real-time slip ratio of the DFIG and the stator power change, inter-partition linkage optimization is carried out on the virtual resistance and the phase calibration angle so as to minimize a dual-power step response fluctuation square mean value, a parameter setting period and a rotor side converter control period are synchronously matched, and all-working-condition stable control is realized.

The invention discloses a dual-frequency positive-sequence impedance modeling method for a network-building type energy storage converter considering frequency coupling. The method comprises the following steps: 1, injecting a dual-frequency positive-sequence disturbance voltage signal at a grid-connected point of the network-building type energy storage converter based on a virtual synchronous machine; 2, establishing a linearized small signal model for each control link of an active-frequency loop, a reactive-voltage loop, a virtual impedance-containing voltage and current double closed loop and the like to form a multi-frequency signal model; and 3, according to the multi-frequency coupling relationship between the current and the voltage, constructing a frequency coupling impedance matrix, and reducing a coupling term into output impedance to obtain the positive sequence output impedance and the negative sequence output impedance of the converter considering the frequency coupling, thereby simplifying the model stability analysis. According to the method, dual-frequency positive sequence disturbance is introduced, the coupling effect between different frequency components is effectively described, the defect that a traditional single-frequency modeling method cannot reflect the multi-frequency interaction characteristic is overcome, and the accuracy and applicability of the impedance model of the network construction type energy storage converter under the multi-frequency disturbance scene are remarkably improved.

The invention belongs to the field of power electronic technology and new energy grid-connected control, and particularly relates to a cooperative control system and method for parallel operation of multiple new energy inverters. The method comprises the following steps: firstly, establishing a small signal model of an inverter parallel system, and analyzing dynamic characteristics of the system under power disturbance; secondly, realizing power decoupling and current sharing control based on a frequency-power droop characteristic; furthermore, coordinated operation of multiple energy sources such as photovoltaic energy and energy storage is realized by monitoring the phase of the direct-current bus voltage and the alternating-current side voltage in real time; the method has high engineering applicability, and high-speed real-time communication between parallel units is not needed; the virtual impedance parameters Rv and Lv have clear physical significance and are easy to preliminarily set according to line parameters; the calculation of the dynamic matching self-adjusting module is linear operation, the requirement for the computing power of a processor is low, and integration and implementation on an existing inverter control platform are facilitated.

The invention discloses a power distribution network voltage fluctuation control method and device considering communication time lag. The method is applied to a distributed photovoltaic power distribution network, the power distribution network at least comprises a cooperative controller and a plurality of weak branches, each weak branch is connected with an impact load and an energy storage converter, and each energy storage converter corresponds to a local energy storage controller; the method comprises the following steps: uniformly modeling communication time lag between the cooperative controller and each local energy storage controller, and distributing the communication time lag to a power distribution link to obtain a power distribution small signal model containing the time lag; constructing a state space model of the energy storage converter; unifying the power distribution small signal model and the state space model of the energy storage converter to a common reference coordinate system to obtain a whole system state equation; and performing voltage control on the power distribution network based on the full-system state equation. The influence of communication delay on the stability of the power distribution network can be eliminated.

The invention discloses a DC micro-grid power buffer safety control method and device aiming at FDI attack, and relates to the technical field of power electronics and power system control. The method comprises the steps of obtaining a block matrix of a DCmGs system node current equation according to the Kirchhoff's current law; adopting Kron simplification to eliminate internal node voltage, obtaining a relation between a port current vector and a voltage vector, and constructing a small signal model of the port voltage vector; based on a small signal model, a linear mapping relation about disturbance of bus voltage to equivalent input impedance of each power buffer is constructed, modeling and linearization are carried out on energy and adjustable input impedance of each power buffer, a network coupling small signal model is constructed, and a second-order high-gain observer is designed; and if the FDI attack exists in the DCmGs system, an anti-FDI attack elastic control law is designed, so that the closed-loop voltage in the DCmGs system and the energy of a power buffer are quickly converged, and buffeting is inhibited. By adopting the method, the DCmGs system can be prevented from buffeting in an unknown FDI attack scene.

This invention belongs to the field of linear periodic time-varying system modeling and analysis technology, and discloses a small-signal modeling method and application for LCC-HVDC systems. The method includes: constructing mathematical models of the segmented and continuous parts of the LCC-HVDC system based on its circuit topology within each operating interval, and integrating these models as the mathematical model of the LCC-HVDC system; linearizing the trajectory of this mathematical model to obtain its small-signal model within each operating interval; designing a small-signal model of the LCC-HVDC system during switching between adjacent operating intervals using the Filippov method; and combining the small-signal models of the LCC-HVDC system within each operating interval and the small-signal models at the switching time to constitute the small-signal model of the LCC-HVDC system, thus completing the small-signal modeling. This invention can accurately characterize the switching dynamics of the LCC-HVDC system, achieving accurate and low-complexity small-signal modeling of the LCC-HVDC system.

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

The invention discloses an energy storage VSG self-adaptive control method based on knowledge and data combined driving. The method comprises the following steps: firstly, constructing an energy storage VSG inverter model to obtain a VSG control equation; building a VSG small-signal model, and setting the value ranges of the rotational inertia and the damping coefficient; then, on the basis of a VSG control equation and energy transfer in VSG grid-connected operation, an angular frequency change rate is obtained, and nonlinear relations exist among the square of the angular frequency change rate, the current change rate of the energy storage equipment, the rotational inertia and the damping coefficient; and finally, based on a data and knowledge combined driving method and a scene division idea, performing offline training on the RBF-PINN neural network. And applying the RBF-PINN neural network after offline training to online training based on knowledge driving, and switching the RBF-PINN neural network in a corresponding scene according to different working conditions to obtain rotational inertia and a damping coefficient. The relation between the energy storage state quantity with obvious change and the VSG control parameters is deeply mined, and the overshoot in the energy storage VSG transient process in online training is obviously reduced.

The invention provides a stability analysis precision method based on an improved phase-locked loop MMC impedance model. According to the improved phase-locked loop structure of the integrated harmonic elimination module, the relation between input and output of an improved part is deduced, and a mathematical model is constructed. Vector expressions of bridge arm equivalent capacitor voltage, bridge arm current and sub-module switching coefficients are obtained through Fourier transform, and an MMC frequency domain steady-state model is constructed. And based on a multi-harmonic linearization method, the model is linearized at a steady-state working point, and a main circuit small signal model after disturbance injection is obtained. And meanwhile, mathematical modeling is carried out on the control system to obtain a small-signal model of a sub-module switching coefficient under disturbance. And solving an alternating current side impedance model adopting the improved phase-locked loop by combining the two types of small signal models. According to the impedance model provided by the invention, the influence of n-order harmonics in the modeling process is effectively eliminated, the precision of the impedance model is improved, and a more reliable reference basis can be provided for stability analysis and parameter design of the MMC system.

The embodiment of the invention provides a DC micro-grid stability control method considering a constant power load, and relates to the technical field of power electronic equipment, and the method comprises the steps: building a state space model of a Boost DC-DC converter; constructing a linear active disturbance rejection controller; dC bus capacitor voltage is collected as a capacitor voltage measurement value; estimating the total disturbance of the system, and outputting a total disturbance observation value; the state feedback control unit executes duty ratio signal generation and output; discretization reconstruction is carried out on the linear active disturbance rejection controller, and a discretization control algorithm adaptive to the digital control chip is generated; capacitor voltage acquisition, disturbance observation value updating and duty ratio signal output are circularly completed according to a set sampling period. The technical problems that in the prior art, control parameters are generally designed and optimized based on a small signal model, large-range disturbance cannot be dealt with, the system is unstable under the large disturbance condition, and the reliability and safety of the micro-grid are seriously affected are solved.

The application discloses a kind of GaN HEMT equivalent circuit model parameter self-adapting extraction method and system, comprising: extracting parasitic parameter value by small signal equivalent circuit parasitic parameter extraction method, establishes initial population;Stripping parasitic parameter in initial population obtains each bias eigenvalue by network analysis, and simulation equivalent circuit S parameter data is obtained by calculation;Judgment is calculated according to S parameter data individual fitness;New individual is generated to replace singular individual in population until population is non-singular;According to the search range of adjustment algorithm of non-singular population;According to the individual selection, crossover, variation rule set to the individual in initial population is carried out genetic calculation, and new genetic individual is obtained;Whether the preset target is satisfied is judged, and the element parameter corresponding to optimal individual is output as the final parameter of small signal model;I-V model is optimized by genetic algorithm, and the weight matrix of fitness function is updated according to model error, and optimization is carried out again to meet the preset target, and the small signal model parameter is combined to establish large signal equivalent circuit model.The application greatly improves the modeling speed of small signal model and the accuracy of large signal model without sacrificing accuracy, which provides key technical support for reliable design of high-power, high-frequency microwave circuit.

The present application relates to LLC resonant converter technical field, specifically to a kind of LLC resonant converter small signal modeling method based on time domain correction;Mainly include the following steps: establishing the equivalent model of LLC resonant converter each element and third-order average value equivalent circuit, LLC resonant converter small signal modeling method is reduced to second-order equivalent circuit by third-order average value equivalent circuit, add disturbance in second-order equivalent circuit, and separate large signal component and second-order small signal disturbance to obtain the analytical form of second-order average value small signal model;The LLC resonant converter small signal modeling method proposed in the scheme considers high precision and ease of use, improves the applicable frequency range, can guide LLC resonant converter controller design and stability analysis, the average value small signal model established by time domain analysis has higher precision, and analytical form transfer function is given, to facilitate practical engineering application.

A parameter adaptive control method and apparatus for a virtual synchronous generator, and an electronic device, relating to the technical field of voltage control. The method comprises: according to a coupling value of a direct current voltage change frequency band of a multi-terminal flexible direct current system during operation, constructing an adaptive direct current voltage droop coefficient function; according to a direct current voltage droop coefficient, calculating a damping ratio of an output port of the multi-terminal flexible direct current system, and according to the damping ratio of the output port and a preset damping ratio, constructing a first optimization objective function; according to differential-mode frequencies of a plurality of converter stations of the multi-terminal flexible direct current system, constructing a second optimization objective function; and constructing a parameter adaptive function according to a small signal model of the multi-terminal flexible direct current system, the first optimization objective function and the second optimization objective function, and solving the parameter adaptive function, so as to obtain a target parameter value of a virtual synchronous generator. The technical problem in the related art that multi-terminal flexible direct current systems exhibit poor stability when encountering disturbances is solved.

The invention provides a bidirectional DC-DC converter control method and system based on a TD3 algorithm. The method comprises the following steps: acquiring a small signal model of the bidirectional DC-DC converter in two working modes of Boost and Buck; constructing an intelligent controller based on a TD3 algorithm; training an intelligent controller, taking the DC bus voltage and the inductive current as state input, taking a system stability index as an award, and obtaining a trained intelligent agent; on the basis of a small signal model, a trained intelligent body replaces a traditional PI controller to output the duty ratio in a current inner loop, and self-adaptive control over the inductive current is achieved; and compensating the output of the traditional PI controller by the trained intelligent agent in the voltage outer loop to realize the adaptive control of the direct current bus voltage. The method does not need a precise mathematical model of the system, can improve the dynamic response of the DC bus voltage under the load change, and has robustness to the change of working conditions.

The invention belongs to the field of power supply and dispatching, and provides a method for optimizing and analyzing the capacity ratio of a follow-up network hybrid system based on a small signal model, which comprehensively considers the voltage and frequency stability of the system so as to determine the optimal capacity ratio of the follow-up network hybrid energy storage system in different power grid scenes. The method comprises the following steps of: firstly, establishing a full-order state space small signal model of a network-following hybrid grid-connected system according to different expressions of a network-following converter control loop; then, a characteristic value analysis method and a participation factor analysis method are utilized to analyze the lowest network construction permeability of the basic requirement for maintaining the system stability under different power grid strengths, and it is revealed that dominant control links influencing the system stability under different working conditions and parameters are different.

The present application belongs to the technical field of fan torsional vibration prediction, and particularly relates to a grid-connected direct-drive fan torsional vibration prediction method, device, equipment and storage medium. The method comprises: constructing a small signal model of the grid-connected direct-drive fan; based on a shafting double-mass block model, deducing the relationship between the port voltage and current signals of the direct-drive fan and the torsional vibration of the shafting of the direct-drive fan when forced oscillation occurs; when forced oscillation occurs, by constructing a wind farm s-domain node admittance model, the transfer function between different grid node ports is obtained, so as to calculate the required grid node port voltage and current signals, taking the calculated voltage and current signals as the input of the small signal model of the grid-connected direct-drive fan, and combining the relationship between the port voltage and current signals of the grid-connected direct-drive fan and the torsional vibration of the shafting of the grid-connected direct-drive fan to calculate the torsional vibration of the shafting of the grid-connected direct-drive fan caused by forced oscillation. It is helpful to timely find and handle potential torsional vibration problems and avoid the occurrence of faults.

The application provides a DC voltage dynamic VSG frequency coupling impedance modeling and stability analysis method, and relates to the technical field of power electronic converter control. The method comprises the following steps: constructing a two-stage VSG system topology; establishing a front-stage DC voltage control model and a rear-stage VSG power control model; based on a harmonic linearization method, establishing a small-signal model considering the mirror frequency effect; deducing a conductance matrix and an impedance matrix containing a DC voltage coupling term; and verifying the system stability through a generalized Nyquist criterion and time domain simulation. The application fuses the DC voltage dynamic and the mirror frequency effect, accurately represents the frequency coupling characteristics of the VSG, avoids the calculation deviation of the traditional model, improves the stability analysis precision, is suitable for new energy power generation, AC / DC microgrid and other scenes, and has important engineering application value.

The application discloses a double-fed fan subsynchronous oscillation additional damping controller based on capacitor current compensation and relates to the field of novel power system stability analysis and control; solves the problems that the existing controller is relatively complex in determining control parameters, lacks universality and operation parameters cannot be modified at will; comprises a small signal model structure based on double-fed induction fan and weak power grid grid connection, and a general phase lead compensation link controller; phase compensation controller parameters are determined through double-fed induction fan voltage and current frequency response curves; the original system control structure can be not changed, the original control parameters of the system do not need to be adjusted, direct DC current signals are obtained from the DC capacitor part of the double-fed fan, control currents are injected in the form of controlled current sources, the rotor side control and the grid side control are decoupled, and the subsynchronous oscillation phenomenon caused by the interaction between the double-fed fan phase-locked loop and the weak power grid is suppressed.

The invention discloses a whole-process modeling method and system for a microwave compound semiconductor device, and relates to the technical field of microwave electronic devices. The method comprises six steps of newly building a device model, importing measured data, extracting parameters of a small-signal model, extracting parameters of a nonlinear current model, extracting parameters of a nonlinear capacitance model and globally verifying the model, so that one-stop parameter extraction covering the whole process is realized, and an analysis and optimization algorithm is integrated to improve the parameter precision; through global verification of five dimensions of multi-bias S parameters, current characteristics, capacitance characteristics, power scanning characteristics and a load traction circle diagram, commercial microwave simulation software is combined, and a Verilog A model capable of being directly loaded is output. According to the method, the problems that in the prior art, the process is not coherent, and verification dimensions are insufficient are solved, the modeling efficiency and the model precision are improved, and accurate model support is provided for high-frequency and high-power electronic devices.

The invention provides a network construction type equipment electromagnetic dynamic modeling method and system considering a network energy storage state, and belongs to the technical field of power system dynamic modeling. The method comprises the following steps: establishing a circuit link electromagnetic scale dynamic model which simultaneously considers instantaneous power transmission and instantaneous energy dynamic states of inductance and capacitance elements according to a grid-connected system topology of a network construction converter; establishing a control link electromagnetic scale dynamic model of the network construction converter; the circuit link electromagnetic scale dynamic model and the control link electromagnetic scale dynamic model are combined, and a network construction converter electromagnetic scale dynamic nonlinear model representing system network energy dynamics is constructed; and carrying out linearization processing on the nonlinear model at a steady-state working point to obtain the electromagnetic scale dynamic small signal model of the network construction converter. According to the method, the coupling effect of network energy dynamic and converter control under the electromagnetic time scale is depicted, and the defects of a traditional steady-state model in broadband oscillation analysis are overcome.

A stability detection method and system for grid-connected and grid-connected converters based on impedance modeling is proposed. This method determines the impedance matrix of the voltage source inverter based on a small-signal model of the voltage source inverter, and establishes a first impedance ratio, a second impedance ratio, and a third impedance ratio with the equivalent impedance matrix of the power grid. If the first impedance ratio does not satisfy the Nyquist stability criterion, the converter is determined to be in a negatively damped state; if the first impedance ratio satisfies the Nyquist stability criterion, the converter is determined to be in a positively damped or underdamped state. The product of the second and third impedance ratios is used as the oscillation damping coefficient. If the oscillation damping coefficient is less than zero, the converter is determined to be in a negatively damped stable state; if the oscillation damping coefficient is greater than or equal to zero and less than the critical damping coefficient, the converter is determined to be in an underdamped stable state; if the oscillation damping coefficient is greater than or equal to the critical damping coefficient, the converter is determined to be in a positively damped stable state. This method accurately describes the dynamic characteristics of the converter under nonlinear and large disturbance conditions.

The invention relates to a computing power center direct current system virtual modulus impedance control and stability domain evaluation method. The method comprises the following steps: establishing a small signal model of the bipolar VSC, converting the small signal model into a modulus space by combining a modulus conversion matrix, and deducing a transfer function relationship among variables in the modulus space; deriving closed-loop output impedance of the bipolar VSC containing the virtual modulus impedance control parameters based on the transfer function relationship; then, in combination with the modulus conversion matrix, lines and loads outside the output port of the bipolar VSC are mapped to a modulus space, and the relation between the output voltage and the output current of the bipolar VSC is deduced; and finally, based on the closed-loop output impedance and the relationship between the output voltage and the output current, deducing an input-output gain matrix of the power center bipolar direct current system, and identifying the stability domain of the system in combination with a generalized Nyquist criterion. Bus voltage oscillation can be suppressed, and effective evaluation of the system stability domain can be realized.

The invention discloses a damping torque-based low-frequency oscillation suppression method for a grid-forming inverter. The method comprises the following steps of: firstly, establishing a small-signal model of a virtual synchronous machine; deriving a damping torque model based on the small signal model; an additional damping branch is introduced into the power control loop to enhance the damping torque of the system; and finally, the suppression effect of the additional damping branch on low-frequency oscillation is verified through simulation. According to the method, a damping torque method and a small signal model are combined, an additional damping branch is introduced into a power control loop, additional damping is provided under the condition that operation of an original system is not affected, and then the low-frequency oscillation phenomenon of the VSG is improved.

The invention discloses a low-inertia coordination control method and system for an ocean micro-grid. The method comprises the following steps: establishing a micro-grid inverter control model based on a virtual synchronous generator; establishing virtual impedance of the virtual synchronous generator according to the inverter control model; performing voltage and current double-closed-loop control on the inverter control model; establishing a small signal model of the virtual synchronous generator, and obtaining the influence of the rotational inertia J and the damping coefficient on the dynamic performance and stability of the micro-grid according to the small signal model and the inverter control model; performing pre-synchronization control based on the virtual synchronous generator; performing adaptive analysis on the rotational inertia J and the damping coefficient according to a small signal model and an inverter control model to obtain output frequency and output power dynamic response data of the micro-grid under the working conditions of sudden increase and sudden decrease of load power; and carrying out adaptive dynamic adjustment on the rotational inertia J and the damping coefficient. According to the method, by improving a virtual synchronous generator control strategy, the stability of the micro-grid under complex working conditions such as wind speed abrupt change, illumination fluctuation and load disturbance is improved.

The invention provides a voltage source converter control method and device, a storage medium and computer equipment. A first small signal model of a voltage source converter and a second small signal model of an alternating current line and a power grid are established through a state-space equation method, and the relation among the small signal stability of the power system, the proportionality coefficient of a hybrid synchronous control loop and the system short-circuit ratio of the power system is obtained through small signal stability analysis. And obtaining a proportionality coefficient value range capable of maintaining small signal stability under different system short-circuit ratios, thereby constructing an adaptive parameter value rule. A proportionality coefficient is determined according to an adaptive parameter value rule, and the proportionality coefficient of the hybrid synchronous control loop can be adaptively changed according to the power grid intensity, so that the voltage source type converter can keep good small signal stability under various power grid intensities. Therefore, the system can stably operate in a strong power grid, a weak power grid and an extremely weak power grid, so that the small signal stability of the power system can be greatly improved.

The application discloses a kind of virtual synchronous machine multi-machine parallel system stability analysis methods based on impedance, it is first equivalent to the small signal model of voltage source system as voltage source, obtain the current of load in the small signal model of voltage source, the stability of the voltage source system is judged by the current of load;Then equivalent to the small signal model of current source system as current source, obtain the voltage of load in the small signal model of current source, the stability of the current source system is judged by the voltage of load;Finally, it is judged that virtual synchronous machine multi-machine parallel system is voltage source system or current source system, virtual synchronous machine multi-machine parallel system is equivalent to corresponding small signal model, obtain corresponding voltage or current to judge the stability of virtual synchronous machine multi-machine parallel system.The application can quickly locate the source or load causing instability problem, and provide the basis for solving the problem.

The invention provides a small signal model of an InP-based HEMT (High Electron Mobility Transistor) device and a parameter extraction method of the small signal model. The model comprises a stray capacitor between gate and drain bonding pads, a stray capacitor between gate and source bonding pads, a stray capacitor between drain and source bonding pads, a gate stray resistor, a gate stray inductor, a drain stray resistor, a drain stray inductor, a capacitor between gate and drain electrodes, a capacitor between gate and source electrodes and a capacitor between drain and source electrodes. An intrinsic gate-source capacitor, an intrinsic gate-drain capacitor, an intrinsic drain-source capacitor, an inter-gate-drain leakage resistor, an inter-gate-source leakage resistor, an output resistor, an intrinsic channel resistor, an intrinsic transconductance and a delay factor are included. Aiming at the working frequency of a device in a millimeter wave band, an improved small signal model is established, distributed model establishment is carried out on parasitic capacitance between bonding pads and parasitic capacitance between tube cores, four auxiliary structures are combined, parameter extraction of parasitic elements such as the parasitic capacitance between the bonding pads and the parasitic capacitance between the tube cores is respectively carried out, and the reliability of the device is improved. Therefore, the precision of the millimeter wave band small signal model is improved.

The invention discloses a VSG stability analysis method and system based on power grid intensity disturbance, and belongs to the technical field of virtual synchronous generator control. According to the method, a small signal model of VSG power grid intensity disturbance is established, the small signal model of power grid intensity change is introduced into a closed-loop control model of a VSG system, and a coupling transfer function between the power grid intensity disturbance and active power and reactive power is deduced; further constructing an oscillation transfer function model, quantitatively analyzing the influence of the power grid intensity disturbance on the electrical quantity of the system, and judging the stability and oscillation transfer effect of the system under the disturbance through the amplitude of a transfer function; according to the method, the blank that a traditional small-signal model does not consider the influence of power grid strength change is filled, the dynamic behavior of the system under power grid parameter perturbation can be accurately predicted, the precision and accuracy of stability analysis are improved, and a theoretical basis and technical support are provided for VSG system control parameter optimization and robustness improvement.

The application provides an M3C impedance modeling method and device based on an HSS method, and relates to the technical field of automatic control. The method comprises the following steps: obtaining a power frequency bridge arm current reference value matrix model of a current inner loop controller, a low frequency bridge arm current reference value matrix model of the current inner loop controller, a power frequency control equation of the current inner loop controller, a low frequency control equation of the current inner loop controller, a first transformation equation small signal model and a second transformation equation; obtaining an equation relationship between port voltage and bridge arm current in a dq0 coordinate system in an M3C small signal model; obtaining a relationship formula between M3C port voltage and M3C port current according to the equation relationship; and performing harmonic state space method processing on the relationship formula to obtain an impedance model of M3C full frequency domain impedance characteristics. The method and device provided in the application embodiment are helpful to further analyze and improve the stability of a low frequency power transmission system.

The application relates to the technical field of wireless power transmission, and particularly discloses a WPT system modeling method based on data driving, which comprises the following steps: firstly, determining the circuit structure and system parameters of the WPT system, establishing a differential equation, then constructing a GSSA model (large signal model) based on the system differential equation, and obtaining a linear small signal model of the system by adding disturbance, further establishing a Hammerstein model based on the large signal model and the small signal model through a data driving modeling method, and performing order reduction to obtain a second-order Hammerstein model, finally constructing an optimization problem based on the second-order Hammerstein model, and finally solving the optimization problem by adopting a method combining the least square method and Newton iteration search, so that the model offset parameters and system communication delay of the WPT system can be estimated more accurately.