270 results about "Space vector" patented technology

The invention discloses a multi-modal data fusion method and system based on a large model, and relates to the technical field of data fusion, and the method comprises the steps: receiving multi-modal data, and carrying out the noise layering filtering and time-space alignment; mapping data to a large model hidden space through each modal lightweight encoder, extracting initial features by using a single-modal pre-training model, and converting the initial features through an adapter to generate a hidden space vector; each modal hidden space vector and a task cue word are received, a fusion feature matrix is dynamically aggregated and generated through a self-attention mechanism and a cross attention mechanism of a large model, and semantic integration of multi-modal information is realized; taking the fusion feature matrix as a soft label, and learning a cross-modal semantic mapping capability through knowledge distillation; the trained model is deployed to the edge through dynamic quantization and pruning optimization, an optimized feature matrix is input into a task-customized lightweight head network, and a final task result is output in combination with multi-modal context information. The method can break through the semantic gap between modals, and improves the fusion efficiency.

The invention discloses a blockage detection method, system and equipment for a flow measurement device and a medium, and relates to the field of blockage detection. The method comprises the following steps: acquiring an original pressure signal and an original flow signal of a to-be-measured flow measuring device, and generating an intrinsic mode function according to the original pressure signal and the original flow signal; extracting a time vector, a space vector and a frequency domain vector of the intrinsic mode function, obtaining an attention weight through a double-path cross attention mechanism, and performing weighted fusion on the time vector, the space vector, the frequency domain vector and the attention weight to obtain a multi-dimensional feature vector; inputting the multi-dimensional feature vector into a pre-trained blockage probability prediction model based on deep learning to obtain a blockage probability value; and constructing a state space according to the blockage probability value, the historical maintenance record and the equipment operation duration, balancing false alarm and leak detection punishment in combination with a reward function, and determining execution operation. By implementing the technical scheme provided by the invention, the accuracy and reliability of blockage detection are improved.

The invention discloses a transformer fault diagnosis and root cause positioning method based on a space-time diagram neural network, and relates to the field of transformer fault diagnosis, and the method comprises the steps: S1, carrying out the preprocessing of the structure information and DGA time series data of a transformer, and obtaining a topological network structure diagram and a DGA time series; s2, obtaining a spatial vector based on a message passing mechanism of a graph convolutional network; s3, a time sequence vector is obtained in combination with a Transform encoder and multi-head self-attention; s4, obtaining space-time fusion features; s5, constructing a multi-task prediction head based on the space-time fusion feature, the fault type historical data and the fault root cause; and S6, carrying out fault detection and outputting a corresponding fault type and root cause positioning result. According to the application, the accuracy of fault type identification can be remarkably improved, and accurate positioning of the fault root cause is realized.

The invention relates to the technical field of inverter pulse width modulation, in particular to a neutral-point potential balance and low common-mode voltage modulation method and system based on an SVPWM inverter, and the method comprises the steps: determining a basic voltage vector based on different switching states of an NPC three-level inverter; respectively determining the midpoint current of each fundamental voltage vector, and determining the fundamental voltage vector causing midpoint potential deviation; combining with a large vector and a zero vector, and performing mode division of a single vector space region; determining an expected current according to the DC side capacitor voltage of the inverter, and constructing a target function based on the expected current; and performing region judgment according to the output synthesized voltage vector, determining a corresponding optimal division mode, obtaining each basic voltage vector of the synthesized voltage vector and a corresponding duty ratio, and determining a switching sequence to obtain a PWM wave. While the neutral-point potential balance and common-mode voltage suppression of the NPC three-level inverter are realized, the switching frequency of the inverter is effectively reduced, and the switching loss is reduced.

Disclosed in the present invention is a variable coefficient equivalent SISO model based stability analysis method for a grid-connected converter system, comprising the following steps: constructing a variable coefficient equivalent SISO model; obtaining a complex space vector open-loop transfer function on the basis of the variable coefficient equivalent SISO model; and obtaining Nyquist curves under different current loop parameters or phase-locked loop parameters on the basis of the complex space vector open-loop transfer function. If the Nyquist curves surround point (-1,0), the grid-connected converter system is stable; and if the Nyquist curves do not surround point (-1,0), the grid-connected converter system is unstable. The present invention performs small disturbance modeling on the grid-connected converter system, considers the influence of mutual coupling between the phase-locked loop and the inner current loop, and derives a variable coefficient SISO open-loop transfer function capable of characterizing an MIMO system. Compared with the technical solution in the prior art that actual working conditions are not considered, the method disclosed in the present invention can more accurately analyze the system stability of the system under variable working conditions and variable parameters.

The invention is suitable for the field of motor driving and control, and provides a dead-beat predictive current control method and system for a direct-current bias vernier reluctance motor, and the method comprises the steps: obtaining the operation data of a target motor, and carrying out the preprocessing of the obtained operation data; inputting the preprocessed operation data into an extended state observer with coupling compensation, and outputting extended state prediction parameters; inputting the extended state prediction parameter into a dead-beat prediction current control model to obtain a dq0-axis regulation voltage; carrying out coordinate transformation on the adjusting voltage of the dq0 axis, and carrying out space vector pulse width modulation to obtain a switching sequence of dual-inverter SVPWM (Space Vector Pulse Width Modulation); acting the switching sequence on a phase winding of the target motor; according to the method, disturbance caused by voltage coupling is considered in the process of predicting current and disturbance; this allows compensation of voltage coupling interference, thereby reducing the influence of interference caused by parameter changes and coupling voltage, and enhancing dynamic response capability.

The invention relates to a method for determining parameters of a double-target time interference stimulating electrode and a stimulating method. The method comprises the following steps of: inputting a lead field matrix, coordinates of two target spots and an electrode frequency; generating a random solution and multiplying the random solution with the lead field matrix to obtain a corresponding high-frequency electric field; inputting a Grossman formula, and obtaining two groups of envelope electric fields with frequencies of # imgabs0 # and delta fHz; performing Hilbert transform and space vector summation on the two groups of envelope electric fields to form a total matrix; constructing a target point matrix; solving the ratio of the average electric field intensity of the target spot matrix to the average electric field intensity of the total matrix, and if the ratio is less than b, removing a corresponding random solution; if the ratio is larger than b, the corresponding random solution is reserved, and a new random solution is generated; and iteration is carried out to a suspension condition, and if suspension is carried out, the reserved random solution is output. Through the arrangement, an electrode feasible solution for simultaneously stimulating double target spots through time interference stimulation can be effectively found.

The invention relates to a high-frequency adaptive space vector pulse width modulation method, which comprises the following steps of: acquiring real-time operating parameters of a motor system to obtain a motor phase current vector and a rotor position signal; carrying out load characteristic identification on the motor system based on the motor phase current vector and the rotor position signal to obtain a load characteristic parameter set; performing frequency domain deconstruction on the load characteristic parameter set to obtain a switching frequency adaptive mapping relation; non-linear optimization is carried out on the space vector division sectors based on the switching frequency adaptive mapping relation, and a corrected space vector positioning result is obtained; and performing dead-zone adaptive compensation on the switching sequence of a power switch tube in the inverter according to a corrected space vector positioning result to obtain a high-frequency pulse width modulation waveform, thereby solving the problems that the quality of the output waveform is reduced, the harmonic distortion is increased, and the accuracy of the high-frequency pulse width modulation waveform is reduced due to the fact that the traditional SVPWM is difficult to realize accurate vector positioning under the nonlinear load and variable working conditions. And stable operation of the motor is influenced.

The invention is suitable for the technical field of flexible power distribution of a power system, and discloses a modular multilevel converter multi-objective optimization method, system and device based on model predictive control and space vector modulation, and a medium. Obtaining an output current reference value and a circulating current reference value; obtaining a reference voltage vector based on the output voltage reference value, and screening out a plurality of groups of redundant voltage vector sequences through a space vector diagram; performing performance evaluation through rolling optimization by combining each redundant voltage vector sequence with a multi-target cost function to obtain an optimal voltage vector sequence; and on the basis of the optimal voltage vector sequence and the corresponding duty ratio, a switching signal for driving each sub-module switching device of the MMC is generated, and multi-target cooperative control is realized. The three targets of reference output current tracking, circulating current suppression and sub-module capacitor voltage balance are met, and the dynamic response capability, efficiency and reliability of MMC system operation are comprehensively improved.

The invention discloses a method for suppressing magnetotelluric mixed noise in a shallow water area. The method comprises the following steps: reading a noisy ocean MT time sequence; setting phase space reconstruction parameters; constructing a phase-space vector to obtain a noisy data matrix; noise priori information is obtained through noise pre-estimation; constructing an original noisy data matrix after noise whitening; performing singular value decomposition to obtain a feature vector and a feature value matrix of a data covariance matrix after noise whitening; selecting a low-order principal component after noise adjustment principal component transformation to reconstruct a denoised data matrix; recovering the denoised data matrix into a time sequence; carrying out Fourier transform to obtain an ocean MT magnetic field component amplitude spectrum, and combining to obtain an ocean MT four-component amplitude spectrum; detecting the frequency point of the pulse in the four-component amplitude spectrum; and setting all amplitudes corresponding to pulse frequency points in the four-component amplitude spectrum to be 0, and performing inverse Fourier transform to obtain a processed four-component time sequence. According to the invention, the ocean magnetotelluric signals can be better processed, and the data quality is improved.

The invention discloses a total space vector vortex generator, which comprises a plurality of tetramer super units which have the same structure and are arranged in a periodic array at equal intervals, and each tetramer super unit comprises two first chiral metamaterial unit assemblies and two second chiral metamaterial unit assemblies which are respectively arranged along diagonal lines; the first chiral metamaterial unit assembly comprises a first patch antenna, a first dielectric layer, a metal backboard, a bonding medium, a second patch antenna and a second dielectric layer which are sequentially arranged from top to bottom; the structure of the second chiral metamaterial unit assembly is the same as that of the first chiral metamaterial unit assembly, and the in-plane rotation angle is different from that of the first chiral metamaterial unit assembly; by rotating the first patch antenna and the second patch antenna of the two chiral super units around the central point, phase distribution is independently designed in four different circular polarization transmission channels, and meanwhile, vortex beam topological charges generated in corresponding channels in transmission and reflection modes are controlled, so that the transmission bandwidth can be expanded, and the transmission efficiency is improved. And the reflection and transmission efficiency is improved.

The invention relates to the field of three-level inverters, and particularly discloses a model-free strong-robustness predictive control method and system for a three-level SNPC inverter, and the method comprises the steps: carrying out the real-time sampling and coordinate transformation of the inverter, and obtaining the current and voltage components under a two-phase static coordinate system; establishing a hyper-local model, enabling the system parameter deviation and the external disturbance to be uniformly equivalent to lumped disturbance, and designing a full-order sliding-mode observer for real-time estimation; calculating a reference voltage vector based on the disturbance estimation value and the extrapolated reference current; and an optimal double-vector combination is selected through space vector optimization, action time is solved, redundant small vectors are selected according to midpoint voltage deviation, and PWM driving signals are generated. According to the method, excellent current tracking performance and low harmonic distortion can still be kept under the conditions of parameter mismatch and working condition change, meanwhile, neutral-point potential balance on the direct-current side is achieved, and the method has the advantages of being small in calculation amount, high in robustness, easy to achieve in engineering and the like.

The invention discloses a single-stage interconnection converter port power distribution method based on a multilayer space vector modulation strategy. The method comprises the following steps: firstly, obtaining a single-stage interconnection converter alternating current side reference voltage vector through an energy management strategy, a power control loop and a current and voltage double closed loop of a hybrid alternating current and direct current micro-grid; then, the single-stage interconnection converter is subjected to equivalent decoupling modeling to form four virtual two-level converters, a four-layer space vector diagram is obtained, scaling factors for decomposing reference voltage vectors are calculated according to given reference power, and therefore the two reference voltage vectors on the alternating current side are decomposed into four independent voltage vectors; and synthesizing the four voltage vectors in a four-layer space vector diagram to obtain the duty ratio of each phase of the four two-level converters so as to obtain the switching sequence of the single-stage interconnection converter.

The invention discloses a high-robustness deadbeat predictive current control method which is suitable for current control of a dual three-phase permanent magnet motor driving system, and belongs to the technical field of permanent magnet motor control. The method mainly comprises the following steps: reconstructing a motor mathematical model by adopting a space vector decoupling matrix and Park transformation to obtain a motor voltage equation under a dqxy axis; designing a linear expansion state observer; a reference value of an output voltage vector is obtained in combination with deadbeat predictive current control; time delay in the digital control system is calculated, and angle delay is compensated; and designing a closed-loop Smith predictor for compensating a time delay link to complete high-robustness dead-beat predictive current control of the dual three-phase permanent magnet motor. The current loop design in the method does not depend on motor parameters, and the method has high parameter change robustness. By introducing the closed-loop Smith predictor, large delay of the system can be effectively compensated, and high-precision current tracking is realized under low switching frequency.

The invention provides a display screen dynamic control method and system, and relates to the technical field of data processing, the method comprises the following steps: constructing a space coordinate system comprising a plurality of entity nodes, the entity nodes comprising a display screen preset angular point, a user binocular vision center and a handheld interaction device; analyzing a relative pose relationship among the nodes by calculating a projection dot product of a space vector corresponding to each node; constructing a dynamic topology network based on the relative pose relationship, and synchronously collecting environment illumination intensity, user fixation point coordinates and user pose data; performing time sequence synchronization and Kalman filtering preprocessing on the acquired multi-modal data to obtain an initial feature set; and generating a spatial calibration coefficient according to the distribution characteristics of the dynamic topology network, and performing normalization compensation on the initial feature set through the calibration coefficient to obtain a calibrated multi-modal sensing feature vector. According to the invention, accurate and intelligent dynamic control is realized.

The invention relates to the technical field of network communication, in particular to an intelligent network card data forwarding method and system based on an FPGA, and the method comprises the steps: after the FPGA receives a data stream, firstly extracting a time interval standard deviation of N data packets as a time feature, executing parallel hash operation on a source IP address and a destination IP address, and mapping the source IP address and the destination IP address into three-dimensional coordinates; splicing the time features and the space coordinates into a two-dimensional matrix; a time vector T and a space vector S are separated from the two-dimensional matrix, the time feature similarity is calculated through cosine similarity, the space similarity is calculated through an Euclidean distance normalization algorithm, and affinity is obtained after weighted fusion; the condition that the affinity exceeds a first preset threshold value is used as a triggering condition for micro-flow slice splitting, and a data label is added to the slice; the FPGA intelligent network card implements heterogeneous channel binding based on slice affinity, and the global crossbar switch realizes non-blocking channel switching according to priority. And the slice splitting is triggered according to the affinity threshold, so that the high-speed transmission efficiency is improved.

The invention relates to an SVPWM (Space Vector Pulse Width Modulation) optimization method for charging pile test equipment and related equipment, and the method comprises the following steps: carrying out the real-time collection of electrical parameters of target charging pile test equipment, and obtaining working state parameters; performing spectral analysis on the working state parameters through a preset fast Fourier transform algorithm to obtain a frequency component distribution diagram; judging whether a harmonic component in a specific frequency range exists in the frequency component distribution diagram or not; if the frequency component distribution diagram does not exist, SVPWM mapping is carried out on the frequency component distribution diagram to obtain a space vector distribution diagram, and coding and modulation optimization are carried out on sector positions and switch states in the space vector distribution diagram to obtain a PWM control instruction sequence; according to the PWM control instruction sequence, an inverter circuit of the target charging pile test equipment is controlled, and output electric energy quality in a specific frequency range is obtained; the technical problem that the quality of output electric energy is reduced due to the fact that a traditional PWM modulation method is difficult to effectively suppress harmonic components is solved.

The invention discloses a dual three-phase permanent magnet synchronous motor hybrid modulation current harmonic suppression method based on voltage compensation. The method comprises the following steps: 1, calculating a required reference voltage vector by a main control unit; step 2, generating and outputting a reference voltage vector by a reference voltage vector calculation module; 3, after coordinate transformation, decomposing the reference voltage vector into two parts: an SVPWM (Space Vector Pulse Width Modulation) signal and a harmonic compensation PWM signal; 4, performing weighted fusion on the harmonic compensation PWM signal and the SVPWM signal in a PWM generation module to generate a PWM signal; and 5, the PWM signal drives the voltage source type inverter, the output voltage of each phase is decomposed according to the direct current bus voltage, the dual three-phase permanent magnet synchronous motor is driven to realize accurate torque control and low-harmonic operation, and meanwhile, the sampling signal is continuously input into the main control unit and the harmonic compensation PWM modulation module to form closed-loop regulation. According to the invention, high-efficiency and low-harmonic motor driving can be realized, and the stability and reliability of the system are greatly improved.

The invention relates to a dual three-phase permanent magnet synchronous motor turn-to-turn short circuit fault adaptive diagnosis method, and belongs to the technical field of motor fault diagnosis. A mathematical model and an adjustable model of a dual three-phase motor turn-to-turn short circuit fault are established, space vector decoupling transformation of a multi-phase motor is combined, a short circuit fault component is introduced into a harmonic sub-plane of a stator voltage equation, and a fault characteristic value is designed by using an x-y current residual error of a real motor and the adjustable model. A fundamental wave amplitude is extracted through orthogonal Fourier transform to serve as a fault degree feature, a model reference adaptive law of an observer and a segmented PI regulator based on a mapping relation between a short-circuit current residual error and a fault turn ratio is constructed, PI parameters are dynamically adjusted according to the rotating speed and the load working condition, and adaptive feedback estimation of the short-circuit turn ratio is achieved. The fault feature extraction precision and real-time performance are improved, the fault-tolerant algorithm is simplified, the parameter design of the disturbance observer is optimized, the problem of diagnosis distortion caused by working condition changes is solved, and a motor monitoring optimization solution is provided.

The invention discloses an ultrasonic orthogonal fusion precise positioning generation method based on space vector synthesis, and the method comprises the following steps: S1, constructing a multi-array ultrasonic transmitting system based on an improved beam forming model, and outputting space vector synthesis wave field data; s2, orthogonally modulating the transmitted signal, executing a synchronous transmission operation, and generating an initial orthogonal fusion ultrasonic signal; s3, receiving an echo signal, constructing a positioning error fitness function, and calculating an initial estimation coordinate; s4, inputting the positioning error fitness into a grey wolf guidance optimization algorithm, and outputting an optimal transmission parameter group; s5, redistributing the optimal transmission parameter group, executing a second synchronous transmission operation, and generating an optimized orthogonal fusion ultrasonic signal; s6, calculating an updated estimated coordinate and a space error value; and S7, feeding back the spatial error value to the grey wolf guided optimization algorithm, and repeating the steps S4 to S7. According to the method, the positioning precision, the emission parameter self-adaption and the closed-loop optimization capability of the ultrasonic system in a complex environment are effectively improved.

The invention discloses a wind power system permanent magnet synchronous motor turn-to-turn short circuit fault diagnosis method considering wind speed fluctuation. The method comprises the following steps: firstly, selecting a current space vector effective value as a diagnosis variable, and constructing a permanent magnet synchronous motor digital twinborn model by establishing a non-electrical quantity expression of a stator current space vector; the model outputs a calculated value of a stator current space vector effective value; and then a self-adaptive threshold value based on the wind speed change rate is designed based on analysis of a residual error between a measured value of a current space vector effective value of the permanent magnet synchronous motor and a model calculation value. And finally, the permanent magnet synchronous motor is monitored in real time in combination with a digital twin model and an adaptive threshold value, a fault phase is determined through a phase current effective value, and the severity is estimated by comparing a current space vector measurement value with a calculation value.

A control device for controlling an electric drive has a basic control loop with a deviation detector (RA), an actuator (IRT), and a controlled system (RS). In the feedback path (FB_G) of the basic control loop, the current of the inverter (INV) is fed back as an actual value (I_EM) in a feedback path. The basic control loop refers to a fundamental angular frequency (ω_G). A harmonic detector (OE, RT_O) is connected downstream of the feedback path (RS). This determines a harmonic component (I_O; I_d(O), I_q(O)) in the actual value (I_EM) or in a power supply signal of the inverter (INV).A counter signal generator (GS_RZ) generates a counter signal (GS) to be fed in, wherein the counter signal generator (GS_RZ) is set up to generate a counter signal (GS) from the harmonic component (I_O; I_d(O), I_q(O)) by adjusting the two vectors of the space vector representation of the counter signal both to minimize the harmonic component (I_O) in the actual value (I_EM) or in the power supply signal and to reduce a harmonic component in the torque.

This inverter control device: switches, in each carrier cycle, the state of a three-phase inverter among four kinds of use vectors such that the number of switching times is minimized; switches one basic space vector included in the four kinds of use vectors to a different basic space vector every 60-degree electrical angle; and switches a zero vector, which is used at the first timing of each carrier cycle, between two kinds of zero vectors every 60-degree electrical angle. When six electrical angles per one cycle of the inverter at the time of basic space vector switching are regarded as 0, 60, 120, 180, 240, and 300 degrees, six electrical angles per one cycle of the inverter at the time of zero vector switching become the angles obtained by adding, to the six electrical angles at the time of the basic space vector switching, the same prescribed angle of not less than 15 degrees but less than 45 degrees.

The invention discloses an overhead line fault diagnosis method, system and device based on space vector conversion and a storage medium, and relates to the technical field of intelligent power distribution, and the method comprises the steps: collecting the normal operation three-phase current data of an overhead power distribution line, and constructing a steady-state feature model; three-phase current data is collected in real time and converted into a space vector sequence, the Euclidean distance between a vector end point and a model center is calculated, and instantaneous offset is extracted. Integrating the offset in a sliding window, calculating a phase rotation rate, generating a multi-dimensional deviation tensor, inputting the multi-dimensional deviation tensor into a fusion function to obtain a misconstruction score, and normalizing the misconstruction score to obtain a misconstruction index; comparing the index with a threshold value, if the index exceeds the threshold value, determining that the disturbance is external transient disturbance, and adjusting the sampling frequency of the current sampling device; according to the method, interference can be effectively identified in a special electromagnetic environment, misjudgment of diagnosis is avoided, maloperation of a protection device is reduced, reclosing operation is guaranteed, and the fault diagnosis accuracy and robustness of a power distribution system are improved.

The invention discloses a method for realizing switching loss optimization based on DPWM and VSV under a load condition, and the method comprises the steps: converting a T-type three-level inverter space vector diagram under an a-b-c coordinate system into an alpha-beta coordinate system, and obtaining the closest three vectors of a synthetic reference voltage vector Vref and the acting time of the closest three vectors; therefore, a foundation is laid for calculating the neutral-point charge Q1 with the clamping position being positive level and the neutral-point charge Q2 with the clamping position being negative level in the current switching period; then, according to a circuit topology structure of the T-type three-level inverter, obtaining a midpoint current corresponding to each vector in the positive and negative small vector switch sequences of each small sector; and finally, judging whether the reference voltage vector Vref is in a controllable region of DPWM neutral-point potential balance or not according to a sign of a product of a neutral-point charge Q1 clamped at a positive level and a neutral-point charge Q2 clamped at a negative level in a switching period when the reference voltage vector Vref is located in the small sector. And if yes, determining the capacitor voltage Udc1 of the upper bus and the capacitor voltage Udc1 of the lower bus at the direct current side of the T-type three-level inverter.

The invention relates to the technical field of motor control in the intelligent power grid industry, and discloses a space vector control method for a twelve-phase permanent magnet synchronous motor flywheel energy storage system, a control circuit of the flywheel energy storage system relates to power electronic components such as various semiconductor field-effect tubes, and the space vector control method is used for high-precision control of a motor. Comprising the steps of S1, twelve-phase space vector decoupling fault-tolerant control, S2, high-order harmonic energy recovery closed loop, S3, quantum annealing parameter optimization layer, S4, flux linkage adaptive observer network construction and S5, 18-dimensional switching vector table construction. According to the scheme, through multi-reference coordinate system transformation and a redundant phase reconstruction algorithm, rapid fault-tolerant response of the twelve-phase motor during a single-phase or two-phase fault is realized, a current path is dynamically recombined during the fault, a negative-sequence current compensation ring is combined, torque ripple is effectively suppressed, and the reliability of the motor is improved under a high-speed charging and discharging working condition. The harmonic distortion rate is detected in real time through the sliding window FFT, the bandwidth of the controller is adjusted, and the problem that the dynamic response of a traditional fault-tolerant strategy is insufficient is solved.

The invention discloses a grid-connected inverter fault ride-through method based on a virtual synchronous generator and related equipment. The method comprises the following steps: acquiring a state variable, a three-phase grid-connected current and a three-phase grid-connected voltage of a grid-connected inverter in real time, and calculating actual active power and actual reactive power when the three-phase grid-connected voltage is abnormal; determining a target voltage positive-sequence component according to the actual active power and the actual reactive power in combination with a power reference value; state prediction is carried out according to the state variables through a preset continuous time state space model, and a plurality of future states corresponding to the prediction interval are generated; minimizing a cost function value of a preset predictive control cost function according to each future state to obtain a target voltage negative sequence component; and performing space vector pulse width modulation according to the target voltage positive sequence component and the target voltage negative sequence component, generating a switching sequence signal and outputting the switching sequence signal to the grid-connected inverter. Therefore, the stability of the output power of the grid-connected inverter is effectively maintained, and the grid-connected electric energy quality and the operation stability are effectively improved.

The invention discloses a three-phase three-wire three-level hybrid modulation switching method and device and a medium, and the method comprises the following steps: obtaining a three-phase sinusoidal modulation wave, and superposing a primary common-mode voltage to obtain a continuous first modulation wave; if the continuous space vector control is executed, comparing the first modulated wave with a carrier wave to form a first duty ratio signal; if the intermittent space vector control is executed, superposing the first modulation wave and a secondary common mode voltage based on a unified coefficient to obtain an intermittent second modulation wave; and according to a specific mode of intermittent space vector modulation, assigning a value to the unified coefficient to obtain a corresponding target intermittent space vector modulation wave. The device and the medium are both used for implementing the method. The method has the beneficial effects that the degree of freedom of the algorithm can be maximized through a PWM unification and coefficient modulation strategy; compared with a traditional mode, the complexity of an algorithm can be effectively reduced, and the reliability of overall code execution can be improved.

The invention provides a model-free predictive current control method and system for a permanent magnet synchronous motor, belongs to the field of permanent magnet synchronous motor control, and avoids dependence on flux linkage and resistance parameters by adaptively switching unknown and disturbance parts of a high-order observer estimation system. Carrying out inductance parameter identification through expansion Kalman filtering, and optimizing a noise variance matrix of Kalman filtering through a particle swarm algorithm; and enabling the dq-axis reference current and the dq-axis feedback current of the motor to pass through a permanent magnet synchronous motor model-free predictive controller based on the self-adaptive switching high-order observer to obtain a dq-axis reference voltage vector, and obtaining an inverter switching signal through a delay compensation module and an SVPWM (Space Vector Pulse Width Modulation) module so as to control the permanent magnet synchronous motor.

The present invention discloses a direct torque control method for a dual three-phase permanent magnet synchronous motor based on duty ratio allocation. By using the method of space vector decoupling, the six phases of the dual three-phase permanent magnet synchronous motor are respectively mapped to three planes to generate four non-zero vectors with different amplitudes; two non-zero vectors are extracted from them and synthesized into two virtual vector sets; the main virtual vector and the slave virtual vector are obtained according to the evaluation parameters; the duty ratios of the main and slave virtual vectors are obtained by processing the evaluation parameters; by synthesizing the main virtual vector and the slave virtual vector into a voltage vector and applying it to the six-phase lines of the dual three-phase permanent magnet synchronous motor within one control period. The control method of the present invention solves the technical problems such as large current harmonic content, large torque and flux linkage fluctuations, and high hardware implementation difficulty of the dual three-phase permanent magnet synchronous motor, reduces the inherent 5th and 7th harmonic contents of the dual three-phase permanent magnet synchronous motor, reduces the torque and flux linkage fluctuations of the dual three-phase permanent magnet synchronous motor, and is convenient for hardware implementation.