39 results about "Frequency grid" patented technology

The invention belongs to the technical field of quality detection, and discloses an electrical automation quality detection method and system. The method comprises the steps of collecting original voltage and current signals of a PCC point of a power grid and performing FFT to obtain a background harmonic frequency set and a background harmonic amplitude set; generating an initial frequency grid based on a preset target frequency band, and generating a sparse frequency grid in combination with the background harmonic waves; calculating the estimated signal-to-noise ratio of each candidate frequency, performing ascending sorting to obtain an injection sequence, injecting sinusoidal signals, collecting PCC point voltage response and total current, and calculating a frequency impedance data pair; performing rational function fitting based on the frequency impedance data to obtain a broadband impedance curve; analyzing the curve, extracting quality characteristic parameters, and performing quality judgment according to the parameters; according to the method, the technical problem that the grid-connected stability quality of a single new energy converter cannot be quickly and automatically qualified in a production line offline detection scene in the prior art is effectively solved.

Embodiments disclosed herein encompass methods, apparatus, and systems for interference management. First resource elements (REs) are configured to enable measurement of interference that affects communications between a first user equipment (UE) and a first network device in a wireless communication system. The first REs include REs that correspond to a subset of REs in a set of second REs, and the set of second REs includes all REs at a time position in a time-frequency grid that are muted for communications by a second UE. Interference mitigation based on the interference measurement may be applied to manage the interference. The interference may include cross-link interference between links in the same wireless communication system, or links in different wireless communication systems such as a terrestrial network and a non-terrestrial network.

A user equipment, UE, is configured for operating in a wireless communication network that utilizes resources of a time / frequency grid. The UE is adapted to report to the wireless communication network a connectivity information associated to a first connectivity option of the UE to the wireless communication network and associated to a second connectivity option of the UE to the wireless communication network; and / or is adapted to receive, during a same instance of time, and decode a first signal received from a first transmission / reception point, TRP, and a second signal received from a second TRP, the first signal and the second signal occupying resources in the same time / frequency grid.

First resource elements (REs) are configured for determination of different components of interference that affects communications between a first user equipment (UE) and a first network device in a wireless communication system. The first REs include REs that correspond to a subset of REs in a set of second REs, and the set of second REs includes all REs at a time position in a time-frequency grid that are muted for communications by a second UE. The first REs further include an RE that corresponds to an RE at a time position in the time-frequency grid, different from the time position of the REs that are muted. The interference may include cross-link interference between links in the same wireless communication system, or links in different wireless communication systems such as a terrestrial network and a non-terrestrial network.

Disclosed is a network device for a wireless integrated radar sensing and communication network, the network device comprising: a resource mapper configured for receiving a data resource allocation message and an enhanced sensing resource allocation message; wherein the resource mapper is configured for selecting a subset of resource elements for communication and coarse radar sensing from a time-frequency grid depending on the data resource allocation message; wherein the resource mapper is configured for selecting a subset of resource elements for enhanced radar sensing from the time-frequency grid depending on the enhanced sensing resource allocation message; wherein the resource mapper is configured in such way that the subset of resource elements for enhanced radar sensing is randomly distributed in the time-frequency grid.

The application discloses a variable-frequency-power-frequency automatic switching energy-saving system and method, and belongs to the technical field of motor control, which comprises the following steps: in the variable-frequency starting stage, a motor is driven to run at variable speed by a frequency converter; when the motor reaches full frequency, high power and stable operation, a control device controls the output voltage of the frequency converter to be synchronous with the grid voltage, and the switching to the power-frequency grid is completed when the phases are consistent; when the load decreases and needs to be reduced, the control device starts the frequency converter to make the output voltage of the frequency converter synchronous with the counter electromotive force of the motor in the power-frequency operation, then performs a back switching operation, the motor in rotation is smoothly connected by the frequency converter, and speed reduction control is implemented, and finally the variable-frequency speed regulation operation state is returned; the application realizes automatic selection of the optimal operation mode according to the actual load, avoids energy loss of the frequency converter in the high-speed area, and ensures that the impact on the motor and the grid in the switching process is minimum.

Methods and systems are described for accessing a network and differentiating a 5G network from a 6G network in a SSB. Methods can include searching for a SSB, detecting a valid PSS sequence, and decoding a SSS by matching a mapping of sequence elements of the SSS to resource elements of an OFDM time-frequency grid to a mapping of SSS sequence elements to resource elements of the OFDM time-frequency grid.

The invention relates to a motor fault diagnosis method based on sparse Bayesian and a one-dimensional neural network. The method comprises the following steps: S1, collecting a motor stator current signal, and carrying out filtering and preprocessing; s2, performing Hilbert transformation on the current signal to obtain an analysis signal; s3, constructing a sparse signal model in the truncated frequency domain and performing frequency grid division; s4, solving the sparse model based on sparse Bayesian learning, and correcting the deviation between the fault frequency and the grid by adopting an off-grid model to obtain an envelope spectrum; and S5, inputting the envelope spectrum into a one-dimensional convolutional neural network to output a motor fault diagnosis result. The method has higher frequency recovery precision, stronger robustness and fault recognition accuracy exceeding 98% in a complex environment.

A coordinated control method for fixed-frequency grid-connected power sources and grid-connected power sources in microgrids belongs to the field of power system automation. Its key features include the following steps: Step a, determining the I-V droop curve parameters of the fixed-frequency grid-connected power source and the P-V droop curve parameters of the grid-connected power source; Step b, data acquisition and processing in the microgrid; Step c, setting the microgrid voltage constructed by the fixed-frequency grid-connected power source and setting the grid-connected power source's grid-connected output power; Step d, coordinated adjustment of the fixed-frequency grid-connected power source and the grid-connected power source based on load characteristics. In this application's technical solution, the fixed-frequency grid-connected power source uses an I-V droop curve to output AC current with a fixed frequency and phase consistent with the synchronization signal. The grid-connected power source tracks the grid phase through a phase-locked loop and adjusts its active power output according to the P-V droop curve. Both the fixed-frequency grid-connected power source and the grid-connected power source allocate active power according to their respective capacities, and each fixed-frequency grid-connected power source allocates reactive power according to its capacity, jointly maintaining the power balance of the microgrid.

The invention discloses a flywheel hybrid offshore floating variable-speed constant-frequency wind power generation system, which relates to the technical field of wind power generation and comprises an impeller, a generator, a flywheel hybrid mechanism, a filter compensation mechanism and a control unit. The flywheel rotating at a high speed has a gyroscopic effect, stable torque generated by rotation of the flywheel can be used for resisting horizontal load effects of wind, waves, flow and the like, and swinging of the floating fan is reduced. And meanwhile, the flywheel hybrid mechanism and the filtering compensation mechanism can ensure that the generator obtains a constant synchronous rotating speed under the variable-speed wind condition, constant-frequency grid connection can be realized without a converter, and the stability and the electric energy quality of the system are improved.

Disclosed is a transceiver device such as a user equipment, UE, configured for operating in a wireless communication network providing a plurality of time resources in a time-frequency grid, the plurality of time resources having a first subset of time resources being sub-band full duplex, SBFD, time resources and a second subset of time resources being non-SBFD time resources; wherein according to a first configuration, the transceiver device restricts communication to one of the first type and the second type; and wherein according to a second configuration, the transceiver device uses both the first type and the second type for communication; wherein based on a received message, e.g., from a base station; and / or based on a determination result obtained by the transceiver device the transceiver device is to operate according to the first configuration or the second configuration.

Disclosed is a transceiver device such as a user equipment, UE, configured for operating in a wireless communication network providing a plurality of time resources in a time-frequency grid, the plurality of time resources comprising a subset of time resources being sub-band full duplex, SBFD, time resources; wherein a SBFD time resources provides for at least one uplink, UL, subband; and for at least one downlink, DL, subband. The transceiver device is to receive instructions indicating a link direction associated with whether to transmit UL or receive DL in a SBFD time resource; and to operate accordingly.

The invention discloses a method for controlling a controlled impedance source of a modular multi-level matrix converter for low-frequency power transmission. According to the control method, on the basis of the idea of a controlled impedance source, the sub-module is equivalently designed to be a frequency division controlled impedance source, energy transfer between impedances is achieved, namely, a power frequency impedance source obtains energy from a power grid, a low frequency impedance source transmits power to a low frequency power transmission system, and therefore stable control over the capacitor voltage of the converter sub-module is guaranteed. And meanwhile, non-communication power frequency / low frequency grid-connected synchronization of the M3C system and self-synchronization among the sub-modules are realized by utilizing the passive synchronization characteristic of the controlled impedance source. The control structure is simple, the information flow of controller interaction and centralized communication can be obviously reduced, and expansion to more quantum modules is easy. According to the control method provided by the invention, the efficiency and safety of the flexible low-frequency power transmission system can be improved, and large-scale grid connection and frequency division power transmission of offshore wind power are realized.

The application provides a non-destructive size measurement method for underground targets by combining frequency coding and half-integer phase control, and belongs to the field of non-destructive size measurement of underground targets. The method solves the problem that the prior art cannot effectively overcome the near distance blind area and suppress the frequency domain sidelobe. The method comprises the following steps: constructing an equal-interval frequency grid; generating a transmission frequency sequence by using a step parameter coprime with the total frequency point number for coding sorting; defining the effective transmission duration of each frequency point time slot, so that the near distance blind area range is determined by meeting the half-integer period condition; in each frequency point time slot, a linear sweep signal is generated, and the cumulative phase of the signal at the end of the time slot is controlled to meet the half-integer circle constraint; the signal is transmitted in sequence, and the echo signal is received synchronously; the complex frequency response of each frequency point is extracted, and after frequency domain coherent synthesis, the phase information is differentially approximated to obtain the group time delay; and the target geometric size is calculated according to the medium propagation speed and the group time delay. The method is used in the field of pipe network detection.

This application discloses a communication method, communication system, and related apparatus. The communication method includes: a first communication device sending first information to a second communication device at a first frequency position; the first information indicating that the first communication device has a first signal to send; the first frequency position is determined based on a first frequency grid, which includes multiple frequency positions, wherein the frequency interval between two adjacent frequency positions is greater than a first threshold; and the first communication device sending the first signal to the second communication device. Embodiments of this application can reduce the power consumption of network devices and terminal devices while ensuring a good network access experience for terminal devices.

An integrated sensing and communication, ISAC, transmitter device (110) comprises a communication interface (113) configured to transmit one or more data communication signals for data communication with an ISAC receiver device (120) using a subset of a plurality of time and frequency resources of a time-frequency grid. Moreover, the ISAC transmitter device comprises processing circuitry (111) configured to allocate a plurality of pilot signals to a further subset of the plurality of time and frequency resources based on a measure indicative of the importance of a sensing performance relative to a data communication performance of the ISAC transmitter device. The communication interface is further configured to transmit the plurality of pilot signals to the ISAC receiver device and / or to a further ISAC receiver device. Thus, the ISAC transmitter device allows adjusting pilot signal allocation depending on the data communication performance relative to the sensing performance.

This application relates to a grid frequency regulation method, apparatus, device, and medium based on a shared DC bus. The method includes: acquiring grid frequency data of each grid connected to a target inverter device; determining, based on the grid frequency data of each grid, whether there is a grid with abnormal frequency in each grid; and, if an abnormal frequency grid is determined to exist, using the target inverter device to adjust the frequency of the abnormal frequency grid. The target inverter device includes one grid-connected inverter and at least two grid-connected inverters, which are connected via a shared DC bus. This method can improve the reliability of grid frequency regulation.

The invention relates to a centralized photovoltaic low-frequency collecting and sending-out system, and the low-frequency collecting and sending-out system reduces the impedance power transmission loss of the sending-out system through a low-frequency photovoltaic module, a low-frequency collecting module, a low-frequency grid-connected module and a low-frequency power transmission system, and achieves the improvement of the sending-out distance and the sending-out capacity. Meanwhile, each photovoltaic field is prevented from being independently and directly connected with high voltage, the complexity of a power transmission line is reduced, the networking difficulty of the power transmission system is reduced, the operation mode of the low-frequency power transmission system is switched through the operation mode switching module, a sending-out channel of the low-frequency collecting and sending-out system plays a role in power regulation and control, and the power transmission efficiency is improved. The utilization rate of the photovoltaic low-frequency collecting and sending-out channel is improved, so that land centralized photovoltaic power generation is efficiently sent out to a load center, and the problem that the power transmission capacity of the photovoltaic channel at night is limited is effectively solved.

In some examples, a method comprises receiving, by a communication apparatus, a downlink transmission comprising a control resource set, wherein the control resource set comprises a set of resources designated for control signaling purposes within a time-frequency grid of the downlink transmission, detecting, by the communication apparatus, a downlink reference signal, DL-RS, transmitted within the control resource set, wherein the reference signal is associated with at least one reference signal configuration, wherein the reference signal configuration comprises a first reference signal configuration and / or a second reference signal configuration, and performing, by the communication apparatus, physical downlink control channel, PDCCH, decoding and / or calculating channel state information based on the detected reference signal.

The application discloses a meshless frequency estimation method for layout unconstrained blade tip timing signal and belongs to the technical field of array signal processing. The method comprises the following steps: setting a sampling model; setting the sampling model of the irregular layout of the blade tip timing signal according to the basic principle of the blade tip timing and the continuous compressive sensing theory; obtaining the rank constraint optimization problem description based on the atomic norm from the sampling model; obtaining the characteristic matrix through the irregular Vandermonde matrix decomposition; solving the rank constraint optimization problem based on the atomic norm through the alternating projection algorithm; and obtaining the frequency estimation value of the signal from the irregular Vandermonde matrix based on the polynomial root estimation method of the root multiple signal classification. The application is based on the basic principle of the blade tip timing and the continuous compressive sensing theory, and the frequency grid does not need to be divided in advance, so that the sensor layout is not restricted by the sparse linear array layout, and the blade tip timing signal obtained is uniform.

The invention discloses a hysteresis current control method and system for a fixed-frequency grid-connected converter, and belongs to the technical field of converter control. The method comprises the following steps: calculating single-cycle variation and influence quantity of voltage, current instruction and hysteresis width of a power grid; calculating a frequency loop compensation gain according to the converter topology; actual switching frequency is detected and compared with an instruction value, and a ring width control instruction is generated through a PI controller; and an actual loop width instruction is obtained by combining the compensation gain, and constant switching frequency control is realized. According to the invention, through multivariable compensation and closed-loop control, the influence of power grid voltage fluctuation, current instruction change and hysteresis width adjustment on the switching frequency is effectively suppressed, the problem of unstable switching frequency of traditional hysteresis control is solved, the advantage of fast dynamic response of hysteresis control is retained, accurate and stable control of the switching frequency is realized, and the switching efficiency is improved. The method is suitable for two-level and three-level converter topologies, and has important engineering application value.

This invention relates to the field of grid-connected technology for medium-frequency grid-connected wind turbines, and particularly to a multi-objective optimization method for the control parameters of the grid-side converter of a medium-frequency grid-connected wind turbine. The method includes: determining the grid-connected model of the grid-side converter of the medium-frequency grid-connected wind turbine, and calculating the range of virtual inertia and virtual damping; establishing a multi-objective optimization function with the optimization objectives of minimizing the overshoot of the power response of the grid-side converter, minimizing the maximum frequency fluctuation of the frequency response, and maximizing the damping ratio of the dominant oscillation mode; constructing a multi-objective optimization model using the parameter combination of virtual inertia and virtual damping as population parameters and the multi-objective optimization function as the applicability function; and solving the multi-objective optimization model using a particle swarm optimization algorithm to obtain the optimal solution for the parameter combination of virtual inertia and virtual damping. This method can improve the control parameters of the grid-side converter, thereby achieving better stability, and can also serve as an initial value selection method for adaptive control.

The invention discloses a neural network modeling method for filter frequency response behavior prediction, relates to the technical field of thin film filter frequency response prediction, and is used for solving the problem of poor physical achievable frequency response prediction of a filter. According to the method, a neural network modeling link from structure parameters, material parameters and process deviation characterization to frequency response is constructed, frequency grid unification and phase continuation processing are performed on a plurality of frequency response labels to form a training sample set, and then a neural network model outputs a physically realizable frequency response characterization parameter set. A plurality of frequency response sequences are generated through a frequency response reconstruction operator, passivity judgment, causality judgment and stability judgment are carried out on reconstructed frequency response in the training process, projection correction and write-back are carried out on a parameter set when the conditions are not met, a prediction result is made to conform to physical achievable constraints, and a projection correction trace is output in the prediction stage. Reliable tracing and abnormal positioning of frequency response prediction are realized, and the efficiency and consistency of design iteration and mass production debugging of the thin film filter are improved.

The application provides a solid oxide fuel cell health state detection method based on a fast impedance spectrum, and relates to the technical field of cell detection. The method comprises the following steps: constructing a logarithmic equidistant frequency grid in a preset frequency band to form a sampling frequency point set; based on electrochemical reaction kinetics and porous electrode mass transfer mechanism, constructing an SOFC aging mechanism model to obtain a mechanism parameter vector corresponding to a target SOFC device; batch solving the SOFC aging mechanism model on different working condition spaces to generate a multi-working condition electrochemical impedance spectrum data set on the frequency grid; training an impedance spectrum reconstruction neural network based on the multi-working condition electrochemical impedance spectrum data set, and inputting a complex impedance value into the impedance spectrum reconstruction neural network to obtain a full-frequency electrochemical impedance spectrum; and performing path analysis based on the frequency domain characteristics in the full-frequency electrochemical impedance spectrum to obtain the health state of the target SOFC device.

The invention relates to the technical field of motor frequency conversion stability control, in particular to a large-interference stability analysis method and system for offshore wind power electromechanical frequency conversion grid connection, and the method comprises the steps: building a nonlinear dynamic model of a motor and a generator set frequency conversion system; performing coordinate translation by taking a steady-state working point of the nonlinear dynamic model as a coordinate origin, and dividing an operation characteristic space into fuzzy subspaces; carrying out local linearization on the model in each fuzzy subspace, and constructing a TS fuzzy model set; constructing a corresponding quadratic Lyapunov function based on the TS fuzzy model set, simultaneously solving a maximum attraction domain boundary, and performing projection to generate a two-dimensional stable operation region graph; and according to the maximum state variable boundary in the graph, adjusting an output power instruction of an offshore wind power system controller to maintain the stability of the system. According to the invention, the problem in the prior art that the system is unstable and the equipment is damaged when the frequency conversion system of the rotating unit is subjected to high-power disturbance is effectively solved.

This application provides a time-frequency and spatial domain joint optimization method and system for integrated OTFS radar-communication signal processing. Specifically, based on the time-varying characteristics and bandwidth of the channel, this application configures the position and density of pilot symbols in the OTFS time-frequency grid, sets the Doppler index range to optimize channel information acquisition, deploys a controllable reflector, constructs a phase modulation matrix based on the target position and communication channel parameters, dynamically adjusts the phase gradient direction, and separates the energy of the target echo and the communication signal. Within the set Doppler index range, frequency offset estimation is calculated, the time-domain sampling points of the received signal are corrected, and a phase correction vector is generated. The main spatial aliasing interference zone is located, and within this zone, the phase correction vector and sub-Doppler parameters are combined, and frequency-domain beamforming weighting and phase rotation compensation are used to suppress symbol interference and spatial aliasing caused by high-speed targets. This application achieves efficient time-frequency and spatial domain collaborative processing of OTFS radar-communication integrated signals.

The present application relates to motor variable frequency stable control technical field, especially offshore wind motor electric variable frequency grid-connected large interference stability analysis method and system, method includes: the nonlinear dynamic model of motor and generator set variable frequency system is established;With the steady state operating point of nonlinear dynamic model as the coordinate origin, the operation characteristic space is divided into fuzzy subspace;In each fuzzy subspace, the model is locally linearized, and the TS fuzzy model set is constructed;Based on the TS fuzzy model set, the corresponding quadratic Lyapunov function is constructed, and the maximum attraction domain boundary is solved and projected to generate a two-dimensional stable operation region map;According to the maximum state variable boundary in the map, the output power command of the offshore wind power system controller is adjusted to maintain system stability.Through the present application, the problem that the prior art cannot maintain system stability and equipment damage when the rotating unit variable frequency system is subjected to high-power disturbance is effectively solved.

The application discloses a kind of offshore wind power low-frequency AC transmission through DRU-MMC frequency conversion grid-connected system and control method thereof.System includes permanent magnet direct drive wind turbine, long-distance AC submarine cable and onshore frequency conversion station, which is composed of twelve-pulse diode rectifier unit (DRU) and modular multilevel converter (MMC) back-to-back frequency converter, which converts low-frequency AC power into power frequency power and connects to the grid.Control method includes: wind turbine grid-side converter adopts power-voltage-current three-layer network type control, power layer is virtual synchronous generator control, and offshore AC system voltage and frequency are autonomously constructed;MMC changes DRU transmission power by adjusting DC voltage, and realizes power balance.The application can effectively construct offshore low-frequency system, realize maximum power tracking, and has inertia response and low-voltage ride-through capability.

Disclosed is a transceiver device such as a user equipment (UE) configured for operating in a wireless communication network providing a plurality of time resources in a time-frequency grid, the plurality of time resources comprising a first subset of time resources being sub-band full duplex (SBFD) time resources and a second subset of time resources being non-SBFD time resources. The transceiver device is to operate based on an association between a sounding reference signal (SRS) transmitted by the transceiver device and a first reference signal.

Disclosed is a transceiver device such as a user equipment (UE) configured for operating in a wireless communication network providing a plurality of time resources in a time-frequency grid, the plurality of time resources comprising a first subset of time resources being sub-band full duplex (SBFD) time resources and a second subset of time resources being non-SBFD time resources; wherein according to a first configuration, the transceiver device restricts communication to one of the first type and the second type; and wherein according to a second configuration, the transceiver device uses both the first type and the second type for communication. Based on a received message and / or based on a determination result obtained by the transceiver device, the transceiver device is to operate according to the first configuration or the second configuration.