737 results about "Frequency deviation" patented technology

The invention relates to the technical field of power system operation and control, and discloses a primary and secondary frequency modulation cooperative control system of a hybrid energy storage coupling wind generating set, which comprises a wind power generation unit, a hybrid energy storage unit and a central cooperative controller. A total power demand including inertia response and primary and secondary frequency modulation is synthesized, a primary and secondary frequency modulation cooperative distribution module generates a dynamic adjustment weight by using an S-type nonlinear function based on a frequency change rate and frequency deviation coupling relationship, and an energy relay compensation mechanism is introduced to fill a power gap in a switching process. And the SOC adaptive constraint and execution module applies direction selective boundary constraint to the state of charge, and controls hybrid energy storage to perform internal energy self-balancing in a frequency modulation dead zone. According to the invention, seamless connection of multi-time scale frequency modulation is realized, frequency secondary drop is effectively prevented, and the frequency support capability and the self-recovery capability of the system are improved.

The invention relates to the technical field of energy storage cooperative control, and discloses an improved energy storage converter grid following control algorithm, which comprises the following steps of: 1, extracting positive sequence and negative sequence components of three-phase voltage of a power grid through a double-sequence decoupling phase-locked loop, and acquiring a positive sequence axis component signal by adopting forward rotation coordinate transformation; and 2, when frequency locking is carried out based on the positive sequence axis component signal, extracting a voltage amplitude corresponding to the positive sequence axis component signal, and inputting the voltage amplitude to a feed-forward passivation module. An active power regulation technical scheme based on a frequency deviation threshold value is adopted, the technical effect of simulating the primary frequency modulation characteristic of a network-forming converter is achieved by detecting the power grid frequency deviation in real time and generating an active power compensation signal, and the defect that traditional network-following control lacks frequency active supporting capacity is overcome. And the converter can spontaneously increase the active power to stabilize the power grid frequency when the power grid frequency drops.

The invention relates to the technical field of power systems, in particular to a UPQC harmonic compensation method and system based on repetitive control, and the method comprises the steps: obtaining a load current signal and a voltage signal of a power distribution network, and extracting a harmonic instruction current based on the load current signal; and inputting the harmonic instruction current into a feed-forward channel constructed based on an adaptive filter, and generating a feed-forward control quantity. The phase and frequency of the voltage signal of the power distribution network are tracked in real time through a digital phase-locked loop, the fundamental frequency of the power grid is accurately solved, and the power distribution network can be accurately controlled. The internal model period and the phase lead compensation amount of the frequency adaptive repetitive controller are dynamically calculated, and the internal model structure of the repetitive controller is always matched with the current power grid frequency by updating the two core parameters in real time, so that the compensation precision decline caused by frequency deviation is avoided; and high-precision suppression of the periodic harmonic waves can be realized in a normal fluctuation range of the fundamental wave frequency of the power grid.

The invention relates to the field of power system automatic control and new energy grid-connected operation, and provides an energy storage-containing new energy field station frequency modulation optimization method based on deep reinforcement learning. The method comprises the following steps: firstly, establishing a frequency response model containing an energy storage new energy field station, constructing a frequency modulation problem into a Markov decision process, and defining a state space containing a charge state and frequency deviation, an action space taking a charge and discharge power instruction as an element, and a multi-target reward function fusing a frequency regulation effect and charge state management; and then designing an intelligent agent network based on a long short-term memory network and an improved soft actor-commentator algorithm, constructing an online training framework with priority experience playback and a sliding time window, and realizing adaptive optimization of the strategy. And finally, generating a robust frequency modulation instruction in real time based on the trained model. Simulation shows that the frequency long-term regulation and control capability and the intelligent level can be remarkably improved, and the frequency modulation performance and the frequency modulation margin are effectively coordinated.

The invention discloses a distributed new energy and energy storage primary frequency modulation multi-agent cooperative control method and system, and belongs to the technical field of power system frequency modulation. The method comprises the following steps: constructing a multi-agent power distribution network simulation environment based on power grid topology and integrated wind power / photovoltaic / energy storage models and constraints; distributing an independent intelligent agent for each unit, and defining an observation space containing information such as frequency deviation and an output adjustment action space; an MADDPG framework containing a shared Critic network and an independent Actor network is built, and cooperative training is achieved through experience playback; designing a comprehensive reward function fusing the frequency, the voltage, the energy storage SOC and the electricity abandoning rate; and outputting a real-time output instruction by using the trained model to realize primary frequency modulation cooperative control. The method can significantly improve the response speed and precision of the distributed energy participating in the primary frequency modulation, guarantees the system safety, reduces the power abandonment rate of the new energy, and meets the power grid safety requirements of the high-permeability new energy.

The invention discloses a power grid broadband oscillation suppression method and device based on adaptive robust control, terminal equipment and a storage medium, and belongs to the field of power systems. The method comprises the following steps: performing fuzzy disturbance classification according to an oscillation mode, an oscillation mode characteristic parameter and a state parameter obtained according to a power grid operation parameter to obtain a disturbance type label and a disturbance degree; the disturbance degree serves as a weighting factor, the initial control parameters are corrected according to the power grid operation parameters, the initial control parameters of the controller and the disturbance type label, and a self-adaptive control strategy is generated after correction; when the disturbance degree is smaller than a disturbance threshold value, the state parameters are regulated and controlled according to a self-adaptive control strategy to update power grid operation parameters; and when the disturbance degree is not less than a disturbance threshold value, taking the minimum sum of the system gain, the frequency deviation and the voltage fluctuation as a target, and regulating and controlling the state parameters under the H infinite robust constraint to update the power grid operation parameters. The problem that in the prior art, broadband oscillation suppression is difficult to adapt to sudden change working conditions is solved.

The invention provides a power distribution network single-high-frequency resonance rapid tracking and adaptive suppression method, a multi-mode dynamic cooperative adaptive suppression system is established based on a PCCVF adaptive method, and the damping characteristics of a power distribution network are remodeled by injecting compensation current into a power distribution network system so as to realize broadband resonance suppression of the power distribution network. The compensation current injection method comprises the following steps: step 1, detecting resonant frequency deviation of a power distribution network through real-time FFT (Fast Fourier Transform); 2, performing dynamic phase angle correction based on a phase prediction residual error of real-time frequency deviation; step 3, constructing a layered impedance remodeling module, and ensuring stable power transmission; 4, establishing a frequency-variable impedance model of the power distribution network based on resonance energy spectral density analysis, dynamically optimizing parameters through fuzzy logic of a bell-shaped membership function, and feeding harmonic compensation current into the power distribution network by using a space vector pulse width modulation technology; according to the invention, single high-frequency resonance can be effectively suppressed, the response and tracking performance of the system is improved, and the spectrum analysis efficiency and bandwidth occupation are optimized.

The invention relates to the technical field of power electronics and power system control, and discloses an intelligent control method and system for a multi-network converter, and the method comprises the steps: collecting the frequency deviation, the power change rate and the voltage amplitude of a power grid in real time, carrying out the filtering and feature extraction, and analyzing the coupling relation, thereby obtaining the parameter coupling strength. And if the intensity exceeds the threshold value, an inertia adjusting signal is generated through a fuzzy logic controller. And calculating a deviation correction value by combining the state evaluation response performance of the converter, and generating an optimization instruction by fusing the frequency deviation. And solving a voltage stability threshold based on the instruction, updating a coupling index, and issuing and executing after verification. And finally, updating the fuzzy rule base by adopting neural network iterative learning according to feedback data, and forming an inertia support frame with self-learning capability. According to the method, the inertia response speed and the operation stability of the multi-network converter system under high-proportion new energy access can be effectively improved, and adaptive cooperative control is realized.

The invention relates to the technical field of micro-grid control, and provides an island micro-grid distributed control method, system and device and a storage medium. Comprising the following steps: performing voltage compensation gain and frequency compensation gain calculation based on droop control output of each distributed power generation unit, droop control output of all neighbor distributed power generation units, and a voltage dynamic tracking error and a frequency dynamic tracking error which are obtained by calculating a microgrid global recovery target to obtain secondary adjustment output; and after corresponding items in the droop control output and the secondary regulation output are summed to generate comprehensive reference output, voltage synthesis is carried out according to the comprehensive reference output to obtain voltage regulation output for output control of a corresponding inverter. Based on a distributed regulation and control mechanism for cooperatively calculating the compensation amount of each power generation unit by using neighbor information and a global recovery target, the dynamic response speed and the power distribution precision can be improved, voltage drop and frequency deviation caused by load disturbance are effectively eliminated, and rapid recovery is realized.

The invention discloses a hybrid energy storage optimization configuration method based on a multi-time scale regulation and control demand, and the method comprises the steps: collecting the operation data of a power system, and obtaining the power fluctuation and the frequency deviation of the power system under a short time scale through a preset high-proportion renewable energy power system model; on the basis of power fluctuation and frequency deviation, the regulation and control requirements of the power system are divided according to different time scales, different energy storage modules are correspondingly configured, and a multi-level collaborative energy storage regulation and control structure matched with the time scales is formed; based on the power system model and the mathematical model of each energy storage module, constructing a hierarchical nested optimization model oriented to multiple time scales; and selecting a typical scene from the operation data by adopting a time sequence clustering method, and obtaining the optimal capacity and power configuration of each energy storage module based on a hierarchical nested optimization model, and obtaining a cross-time-scale collaborative operation strategy. The global optimal configuration is realized by establishing a multi-time-scale collaborative hierarchical nested optimization architecture.

The invention provides a cascade AGC (Automatic Gain Control) frequency modulation regulation control optimization method, which comprises the following steps: acquiring frequency deviation and tie line power deviation in a power system in real time, calculating a regional control error ACE based on the two deviations, and decomposing the ACE into a frequency deviation component and a tie line power deviation component; calculating a ratio coefficient of the frequency deviation component in the ACE and a ratio coefficient of the tie line power deviation component in the ACE; acquiring a climbing rate and an adjustable capacity of each frequency modulation unit, and performing normalization processing on the climbing rate and the adjustable capacity; calculating the rate-capacity double weight of each unit through a dynamic weight formula in combination with the ratio coefficient, the normalized climbing rate and the normalized adjustable capacity, and distributing frequency modulation power to each unit according to the normalized weight; in the operation process, on-line self-adaptive adjustment is carried out on dynamic weight calculation and unit adjustment related parameters according to system performance indexes.

The invention relates to the technical field of power dispatching, in particular to an energy storage combined frequency modulation control method and system in a source-network-load-storage integrated regional power grid, and the method comprises the steps: dynamically calculating the adjustable capacity of each resource, dynamically aggregating the total adjustable capacity of the system, sensing the multi-dimensional frequency situation and calculating the adjusting power, and selecting a frequency modulation mode and generating a power distribution strategy. And generating a splitting and isolated network frequency modulation stability control strategy and performing system grid-connected resynchronous operation. The method is suitable for guiding power supply, energy storage and load all-resource collaborative frequency modulation strategy generation in a regional power grid. For consistency of frequency deviation, frequency change rate and active power flow direction, multi-dimensional frequency situation awareness is constructed, power distribution strategies in different modes are generated based on a total adjustable capacity interval of a system, and a frequency stability control and grid-connected resynchronization strategy after splitting is given when the frequency and the adjustable interval exceed limits. Accurate matching of all-resource collaborative frequency modulation and strategies in a regional power grid is realized, and the frequency modulation response speed of the system is improved.

The invention discloses an active power and frequency coordination control method for a wind storage combined system, and belongs to the technical field of electric power system operation and control. The problems that in the prior art, due to wind power and load uncertainty, the frequency control effect is poor, energy storage life management is insufficient, and long-term and short-term control instructions are disjointed are solved. The problem is solved by constructing a three-layer collaborative architecture of a predictive optimization layer, a real-time coordination control layer and an execution layer: the predictive optimization layer randomly optimizes and generates a reference state track and a frequency modulation capacity instruction of an energy storage unit based on a scene method; the real-time coordination control layer utilizes a deep reinforcement learning coordination controller, synthesizes frequency deviation, SOC compensation signals and frequency modulation capacity reservation instructions, and dynamically distributes active power of a fan and energy storage; and the execution layer realizes rapid issuing of the instruction. The method is mainly used for active power coordination and frequency support of a wind storage combined system in a high-proportion new energy power system, and can effectively delay energy storage life attenuation while stabilizing frequency fluctuation.

The invention relates to the technical field of supervision control, in particular to a new energy storage optimization control method and system, and the method comprises the following steps: collecting a grid-connected point voltage amplitude deviation, a frequency deviation and a voltage total harmonic distortion rate, and generating a power grid stress index; according to the method, the multi-dimensional state vector is constructed by collecting the grid-connected point voltage amplitude deviation, the frequency deviation and the total harmonic distortion rate to generate the stress index reflecting the power grid operation pressure, accurate quantitative sensing of the power grid state is achieved, the power grid supporting gain coefficient is dynamically generated according to comparison of the index and the preset threshold value, and the power grid supporting effect is improved. And the total required power to be responded by the energy storage system is adjusted and determined, so that the power support strength is matched with the actual demand of the power grid, and insufficient response or excessive response is avoided.

The invention relates to the technical field of distributed energy and micro-grids, in particular to a distributed energy output high-precision prediction model, which comprises the steps of collecting data and generating a power fluctuation probability envelope; constructing a complementary voltage-stabilizing virtual subgroup with a negative correlation compensation characteristic through a sequential sequence comparison algorithm; based on a power grid agent model and a kernel function SHAP algorithm, quantizing marginal contribution values of residual disturbance power of each subgroup to frequency deviation of the common connection point; performing a non-linear mapping on the contribution value to generate a virtual impedance correction parameter; and finally, through a layered decoupling closed-loop correction architecture, determining predicted power regulation and control vacancy and generating a compensation instruction. According to the method, the complementarity and the disturbance contribution of each heterogeneous power supply are quantified, so that the high-precision prediction of the distributed energy grid-connected stability influence is realized.

The invention discloses a distributed hierarchical cooperative control method and system for an optical storage all-in-one machine cluster, and the method comprises the steps: collecting voltage, frequency and harmonic data, and calculating a global voltage deviation, a frequency deviation and a harmonic content consensus value; calculating a unified transient support index judgment working condition based on the consensus value, and generating a global virtual inertia and impedance demand in emergency; calculating a schedulable potential index of each node based on local data of the node; distributing the requirements for the first time according to the indexes, and adjusting the parameters of the inverter to execute control after the nodes which do not meet the requirements are distributed for the second time; a three-layer architecture of'decision-aggregation-execution 'is constructed, a global state consensus and a nearby-global secondary distribution strategy are realized in combination with a consistency algorithm, a set of'local priority-adjacent support-global bottom-taking' allocation mechanism is formed, the adaptive capacity of the optical storage cluster to complex working conditions and the regional power quality are improved, and the optimal power quality is improved. And the grid-connected stability and the absorption level of the large-scale distributed energy in the weak power grid environment are remarkably improved.

The invention discloses an MMC intelligent setting and cooperative control method and system based on deep reinforcement learning, and relates to the technical field of power transmission system regulation and control, and the method comprises the steps: obtaining the current operation state data of a converter in a power transmission system, the current operation state data comprising a system frequency, a frequency reference value, a frequency deviation and a frequency change rate; establishing a third-order active closed-loop small signal transfer function based on an active transient feedback compensation algorithm, and decoupling a damping coefficient and a primary frequency modulation coefficient in VSG control through the third-order active closed-loop small signal transfer function; inputting the current operation state data into the trained DDPG intelligent agent for processing, and obtaining an optimization result of the virtual inertia; the optimized virtual inertia is applied to a rotational inertia control link of VSG control, and self-adaptive adjustment of the virtual inertia is carried out through the trained DDPG intelligent agent; the problem that control parameters of a traditional virtual synchronous generator VSG are fixed and are difficult to adapt to system operation state changes is solved.

The invention belongs to the field of automatic control of hydroelectric generating sets, and particularly discloses a primary frequency modulation optimization control method and system based on power opening nonlinear prediction.The method comprises the steps that frequency deviation is converted into primary frequency modulation power variable quantity, the power variable quantity and a basic power set point of a set are added, and a dynamic power target is obtained; integrating the power deviation signal to obtain a power integration opening reference instruction; taking the dynamic power target and the unit water head as input of a feed-forward model, and obtaining a feed-forward dominant opening instruction; the opening degree deviation value is input into a PID controller, and a feedback opening degree correction instruction is generated; and a guide vane opening given value is obtained based on the feed-forward dominant opening instruction and the feedback opening correction instruction and serves as a given signal of a guide vane position control loop. According to the invention, through nonlinear prediction and a unique feedback structure, high self-adaption to the working condition change of the unit is realized, and the rapidity, consistency and robustness of the primary frequency modulation response of the unit are remarkably improved.

The invention relates to the technical field of satellite signal processing, and discloses a multi-constellation satellite signal intelligent identification and adaptive acquisition method and system. The method comprises the following steps: performing short-time Fourier transform on a received signal to extract a frequency trajectory matrix, calculating a Doppler frequency shift rate and an acceleration, inputting a multi-task neural network in combination with modulation domain characteristics, and outputting constellation category and interference type identification results, when a low-orbit satellite is identified, a carrier frequency deviation track and uncertainty are predicted through a long-short term memory network, the frequency of a numerical control oscillator is adjusted in advance according to a prediction result, a search window and integral time are dynamically set, and corresponding anti-interference strategies are executed for different interference types. And periodically monitoring the signal quality index, and triggering strategy upgrading when the performance improvement rate is lower than a threshold value. According to the invention, the signal capture success rate and tracking stability in a multi-constellation mixed environment are improved.

Disclosed in the present application are a method and apparatus for regulating the power of an offshore wind farm energy storage system on the basis of the state of charge. The method in the present application comprises: acquiring a power grid frequency and the state of charge of an offshore wind farm energy storage system, and on the basis of the power grid frequency and the state of charge, acquiring a power grid frequency deviation and a state-of-charge recovery demand, respectively; determining whether the power grid frequency deviation is within a preset power grid frequency dead band, if the power grid frequency deviation is within the power grid frequency dead band, in view of the power grid frequency deviation and the state-of-charge recovery demand, acquiring an inertia power regulation and control amount of the energy storage system by means of a fuzzy control algorithm combined with a preset adaptive inertia frequency control model, otherwise, in view of the power grid frequency deviation and the state-of-charge recovery demand, acquiring the inertia power regulation and control amount by means of the adaptive inertia frequency control model; and on the basis of the inertia power regulation and control amount, regulating and controlling the inertia power of the offshore wind farm energy storage system. By means of the present application, the level of refinement and accuracy of a regulation and control process for an energy storage system can be improved.

The invention relates to the technical field of power system control and energy storage, and discloses an active power compensation control method in a network following mode based on a direct-hanging energy storage converter system, and the method comprises the steps: calculating a frequency deviation between a load side instantaneous frequency and a rated frequency; calculating an initial active power compensation reference value according to the frequency deviation and the frequency deviation change rate; synchronously performing first-order inertial filtering and integral operation with amplitude on the initial active power compensation reference value to generate a final active power compensation instruction; adding the final active power compensation instruction and a preset steady-state active power reference value to obtain a total active power reference value of the converter; and taking the total active power reference value of the converter as a reference value of an active power outer ring, and generating a modulation signal of the converter through power control and current control. According to the invention, the virtual inertia link can suppress the rapid change rate of the frequency, and the virtual droop link provides steady-state power support, so that the energy storage system shows a friendly grid-connected characteristic similar to that of a synchronous generator.

The invention relates to the technical field of power system stability control, and discloses a hybrid synchronous phase modifier quick response coordination control system with inertia support. According to the invention, wide-area data such as voltage phase, frequency deviation and the like are collected and verified through the data sensing module; the modal evaluation module calculates a global motion modal cooperation coefficient G to quantify the dynamic cooperation degree of the system; the coordination control module dynamically switches an emergency instability or preventive damping mode based on G, and generates a coordination control instruction of the phase modifier and the SVG; and the execution feedback module forms a closed loop and optimizes parameters, and realizes efficient response in combination with a layered distributed architecture. According to the invention, deep cooperative control of the two is realized, the disturbance resistance and stability maintenance capability of the power system are improved, and the method is suitable for a power grid with high-proportion renewable energy access.

The invention discloses a hydroelectric generating set power active control method, system and device based on frequency prediction and a medium, and belongs to the technical field of power control, and the method comprises the steps: collecting basic operation data of a hydroelectric generating set adjusting system in real time, and carrying out the preprocessing of the basic operation data; time sequence characteristics of the power grid frequency data are extracted, and a neural network is adopted to generate a power grid frequency prediction sequence in a future time window; the power grid frequency prediction sequence is converted into a dynamic power feed-forward compensation amount, feed-forward compensation amount optimization calculation is carried out, the feed-forward compensation amount is superposed to the output end of a feedback controller, and a composite power instruction input value hydroelectric generating set is formed; and updating a neural network input sequence in each control period by adopting a rolling time domain prediction strategy, dynamically correcting a future prediction result, and realizing controlled quantity updating based on actual frequency deviation. According to the method, the compensation weight is dynamically updated by using the online adaptive algorithm, the prediction error and the system performance target are considered, and the compensation amount distribution is optimized.

The invention relates to the technical field of network data security, in particular to a power fgOTN power low-delay secure transmission method. Obtaining a service bearing network topology and link transmission parameters, and constructing a network connection matrix; simulating a flow redistribution process after a fault of a single node, and calculating a topology betweenness centrality index of the substation node; the method comprises the following steps: analyzing payload contents of power business data frames at a fgOTN mapping preceding stage, extracting continuous monitoring features and discrete control features, and calculating a real-time business criticality index of each data frame in combination with a frequency deviation and a voltage fluctuation state of a current network; establishing a two-dimensional decision matrix, and generating a defense strategy according to mapping positions of the topological betweenness centrality index and the criticality index value in the matrix; processing the service data according to the generated defense strategy, and mapping the service data to a fine granularity time slot of the fgOTN; and embedding a security state signaling in the frame overhead, and sending the security state signaling to opposite-end equipment through an optical transmission unit.

The invention discloses a transformer winding deformation diagnosis software system based on frequency domain transfer function analysis, relates to the technical field of transformer winding deformation diagnosis, and is used for realizing accurate online diagnosis of winding deformation. The frequency response data quality control module performs fast Fourier transform and adaptive filtering on the original frequency response signal uploaded by the distributed detection terminal to generate a transfer function data set of which the signal-to-noise ratio reaches the standard; the transfer function multi-dimensional analysis module performs longitudinal deviation and transverse consistency analysis on the data set, identifies resonant frequency deviation, amplitude change and quality factor drift, and generates a deformation suspicious degree index; the deformation trend prediction module calculates a change trend slope based on a historical suspicious degree sequence and identifies a sensitive frequency band; and the fault mode identification module carries out spectrum refinement analysis on the sensitive frequency band, matches the sensitive frequency band with a typical fault feature library, and outputs a fault type and confidence evaluation. Multi-terminal synchronous monitoring, dynamic prediction and intelligent fault identification are realized, and technical support is provided for predictive maintenance of the transformer.

The invention discloses an AGC information physical system reliability verification method and system, and relates to the technical field of power dispatching automation. The problems that an existing AGC system only adopts a static operation mode and an ideal communication condition in a simulation test, and coupling response of continuous operation and sudden disturbance of a power grid under a long time scale is difficult to reproduce truly are solved. The state evolution under event driving is realized by constructing three types of simulation event sources of a time sequence operation sample, a master station control instruction and external disturbance and setting a priority mechanism of external disturbance gt, master station instruction gt and time sequence propulsion; an uplink channel fault model is introduced to simulate on-off, delay and errors of measurement data, and a downlink channel fault model is introduced to simulate transmission abnormity of a control instruction; closed-loop simulation of frequency response and electrical quantity updating is realized by combining promotion of a rotor motion equation and dynamic load flow calculation; and finally, by analyzing indexes such as frequency deviation, tie line deviation and control response delay, comprehensive reliability evaluation of the AGC system in a complex information physical environment is completed.

The invention discloses a method, device and equipment for determining parameters of a proportional resonance controller and a medium, the proportional resonance controller is applied to a current controller of a three-phase grid-connected inverter, the parameters of the proportional resonance controller comprise a proportionality coefficient, a first damping coefficient and a second damping coefficient, the first damping coefficient is greater than the second damping coefficient, and the second damping coefficient is greater than the first damping coefficient. The three-phase grid-connected inverter further comprises a filter. The proportional resonance controller is low in parameter coupling, can be independently designed, and is simple in engineering implementation; in the target open-loop transfer function, the proportionality coefficient determines the basic proportional gain, the damping coefficient controls the attenuation speed of the corresponding resonance factor, the difference between the first damping coefficient and the second damping coefficient can influence the gain bandwidth, and the larger the difference between the first damping coefficient and the second damping coefficient is, the more significant the attenuation speed difference between the second resonance factor and the first resonance factor is. The wider the high gain interval at the specific frequency of the power grid is, the higher gain is still kept even if the frequency of the power grid fluctuates, and the adaptability and robustness to the frequency deviation of the power grid are improved.

The invention relates to the technical field of offshore wind power grid connection, in particular to a low-frequency oscillation suppression method for an offshore wind power synchronous machine grid connection system, which comprises the following steps: acquiring inherent parameters of the synchronous machine grid connection system and active power reference instructions of each fan of an offshore wind power plant; according to the inherent parameters, control parameters of a preset damping controller are determined, and the damping controller is configured based on the control parameters; acquiring an actual operation frequency signal of the offshore low-frequency power grid in real time, and comparing the actual operation frequency signal with a preset rated frequency of the offshore low-frequency power grid to obtain a frequency deviation signal; inputting the frequency deviation signal into a configured damping controller, and outputting a damping power instruction; and superposing the damping power instruction and the active power reference instruction to generate an active power control instruction. According to the invention, the low-frequency oscillation of the new energy synchronous machine grid-connected system can be effectively suppressed, and meanwhile, the situation that the grid-connected safety is threatened due to the great fluctuation of the terminal voltage of the motor caused by suppression measures is avoided.

The invention discloses a pulling and lifting cable frequency detection and cable force measurement method and system based on a millimeter wave radar, and belongs to the field of pulling and lifting cable force measurement. The method comprises the steps that vibration signals are collected through the millimeter wave radar to obtain complex data streams, time-frequency analysis is conducted on the complex data streams, and an interference model is established; the method comprises the following steps: reconstructing a noise-reduced vibration signal by adopting adaptive filtering, extracting candidate vibration frequencies through power spectral density estimation and spectral peak detection, calculating corresponding stability scores, and obtaining a first verification factor used for evaluating wind disturbance and a second verification factor used for evaluating vibration frequency deviation; according to the method, through multi-source sensing data fusion and self-adaptive signal processing, complex environment interference is effectively overcome, non-contact high-precision cable force measurement is achieved, and the method has the outstanding advantages of being high in anti-interference capacity, high in measurement reliability and the like.

The invention relates to a primary frequency modulation control method for a pumped storage coupled compressed air energy storage system, and the method comprises the steps: building a frequency modulation control model based on the core component information and operation constraints of the pumped storage coupled compressed air energy storage frequency modulation system, building a state space model, and building a discretization state equation, establishing a comprehensive optimization model by taking the minimum power grid frequency deviation and the system operation cost as targets; and establishing a multi-parameter planning model based on the reservoir level, the gas storage pressure, the frequency deviation and the comprehensive optimization model, and converting a hierarchical model prediction control problem into multi-parameter quadratic programming to form a self-healing frequency modulation strategy to perform power output tracking control. Therefore, the problem that the frequency modulation performance is limited due to the fact that a water pressure system and an air pressure system in the hybrid power station are complex in coupling and large in response difference, and a related linear control strategy or a single control framework is difficult to achieve rapid response and accurate coordination of the hybrid system in the primary frequency modulation process is solved.