243 results about "Pitch control" patented technology

The invention belongs to the technical field of wind power generation, and discloses a wind driven generator multi-drive variable pitch control method based on big data, which comprises the following steps of: constructing a multi-source data acquisition network covering an environment, a unit, a power grid and a driver, and combining preprocessing means such as denoising and standardization and feature extraction methods such as principal component analysis; high-quality input is provided for a short-term prediction model; the model can accurately pre-judge wind conditions and power requirements in the future 10-30 minutes, and is matched with a global optimization algorithm to dynamically adjust a variable pitch strategy, so that the wind driven generator can still keep stable power output under complex working conditions of gust, power grid fluctuation and the like, and particularly has outstanding performance in areas with unstable wind resources. According to mechanical coupling characteristics of the multi-drive variable pitch system, mechanical parameters such as a gear transmission gap and shafting rigidity are fully included in global optimization, and power output, mechanical fatigue and load distribution are balanced through a multi-objective optimization algorithm.

The invention provides a self-adaptive variable-pitch control method and system based on turbulence intensity dynamic compensation, and relates to the field of wind power generation. Firstly, a real-time turbulence data set in the operation environment of a wind turbine generator is obtained, and the real-time turbulence data set comprises multi-dimensional turbulence characteristic units which are continuously collected and provided with time sequence marks; performing feature extraction on the real-time turbulence data set to obtain turbulence feature distribution containing spatial distribution features and dynamic change features, then generating a dynamic compensation strategy containing a related compensation parameter set according to the turbulence feature distribution, and adjusting control parameters of a preset variable pitch control model based on the dynamic compensation strategy to obtain the variable pitch control model. And finally, a pitch angle adjusting mechanism of the wind turbine generator is controlled through the corrected parameters, self-adaptive adjustment of the pitch angle is achieved, and therefore the operation stability and the output power stability of the wind turbine generator under the complex turbulence working condition can be improved, the damage risk of parts can be reduced, and the service life of the wind turbine generator can be prolonged.

The invention relates to the technical field of wind power generation, and discloses a variable-pitch control method, device, equipment and product for a floating type wind turbine generator. A wind turbine generator model is constructed by comprehensively considering multiple factors such as aerodynamics, hydrodynamics and mooring dynamics, and a gain scheduling control model is introduced into a preset PI control method; the method can adapt to different working conditions, effectively overcomes the limitation of the traditional PID control in the complex dynamic environment of the floating wind turbine generator, reduces the power fluctuation, and reduces the structure resonance risk. A preset platform pitching value is introduced into expert PID control, and Kohmann coordinate transformation is combined, so that the negative damping problem of a unified variable-pitch floating type fan is solved, and accurate distribution of control signals is realized. And finally, through the control combination of unified variable pitch and independent variable pitch, the pitching amplitude is reduced, the blade load is reduced, the stability and safety of the floating type wind turbine generator are remarkably improved, and reliable operation of the generator is guaranteed.

The invention discloses a wind turbine generator self-adaptive control method, medium and system based on environmental turbulence, and the method comprises the steps: S1, collecting the power of a generator and the current pitch angle in the normal operation process of a wind turbine generator; s2, estimating the real-time wind speed based on the power of the generator and the inherent parameters of the unit; s3, calculating real-time environmental turbulence intensity according to the real-time estimated wind speed; s4, inputting the real-time environmental turbulence intensity and the current pitch angle into a fuzzy controller, and calculating a variable pitch control parameter coefficient according to a preset fuzzy rule; and S5, based on the variable-pitch control parameter coefficient, the variable-pitch control parameter is adjusted to carry out variable-pitch control, and self-adaptive stable operation of the unit is achieved. According to the method, no hardware needs to be additionally installed, unit load impact and rotating speed fluctuation caused by large turbulence can be effectively restrained, and on the premise that it is ensured that the limit load of key components does not exceed the limit, the operation stability of the unit is improved, the power generation loss is reduced, and cost reduction, efficiency improvement and safe and stable operation are achieved.

The method aims at solving the problems that in a wind power generation system, due to modeling errors of a prediction model in model prediction independent variable pitch control, the load of a blade root of a fan is too large, and output power is unstable. On the basis of model predictive control (MPC) independent variable pitch control, a model predictive independent variable pitch control method integrating deep deterministic policy gradient algorithm (DDPG) reinforcement learning compensation is provided, so that the modeling error of an MPC predictive model is reduced, the load reduction effect is improved, and the stability of output power is enhanced. And a DDPG compensator is designed, so that an intelligent agent continuously learns through a trial-and-error and feedback mechanism, thereby dynamically compensating a modeling error and improving the load reduction performance of MPC independent variable pitch control. According to the invention, the output power of the fan can be more stable, and the fluctuation of blade root load can be effectively reduced, so that the service life of the fan is prolonged, and the operation reliability of the system is improved.

The invention discloses an intelligent variable pitch control method, system and equipment for a wind generating set, and relates to the technical field of wind generating set control, and the method comprises the steps: synchronously collecting multi-source data in real time through a multi-source heterogeneous sensor array, constructing a dynamic load spectrum matrix, and carrying out nonlinear optimization; an optimal pitch angle sequence is generated to drive a variable pitch execution mechanism, meanwhile, the blade stress change rate is monitored in real time, and an aerodynamic load-structure response coupling factor is calculated; when the factor exceeds a safety threshold, the pitch angle command is reconstructed and the pitch angle is forcibly adjusted to a preset safety angle. The technical problems that the power generation efficiency and the structure safety are difficult to consider under the complex turbulence condition and a safety protection mechanism under the over-limit working condition is lacked in the variable pitch control of the existing wind generating set are solved, and the aim that the power generation efficiency and the structure safety are effectively improved through nonlinear optimization control and introduction of an over-limit triggered standby control path is achieved. And the technical effect of dynamic unification of power generation efficiency and structural safety in a complex turbulence environment is achieved.

The invention discloses a wind power plant equivalent frequency response modeling method considering working condition uncertainty and an equivalence method, belongs to the technical field of power system modeling and equivalence, and aims to solve the problem that no method capable of considering the working condition uncertainty of units in a wind power plant to perform equivalent aggregation on the frequency response of the whole wind power plant exists at present. According to the method, modeling is carried out on the wind speed distribution uncertainty in a wind power plant by adopting a probability method, a wind power plant wind speed distribution scene is generated based on a three-parameter Weibull distribution function, and the working condition uncertainty of each unit is represented; dividing the wind power plant into a non-frequency modulation area, a comprehensive inertia and overspeed load shedding control area and a comprehensive inertia and variable pitch control area according to the wind speed distribution and the corresponding wind speed during fan output; and based on a partitioning result, determining an equivalent influence coefficient and an equivalent control coefficient by utilizing parameters of each wind turbine generator, obtaining a wind power plant equivalent frequency response model considering working condition uncertainty by combining a wind turbine generator frequency response model, and realizing equivalence based on the model.

The invention relates to the field of wind driven generators, and particularly discloses a floating type vertical axis wind turbine multi-partition variable pitch control strategy which comprises the steps that S1, basic parameters and operating condition parameters of a unit are obtained; s2, establishing an aerodynamic model based on a double-disk multi-flow management theory and a superposition wind speed method; s3, measuring parameters through a sensor, and calculating a theoretical attack angle of the blade; s4, establishing a multi-partition pitch angle change function based on the theoretical attack angle; s5, constructing an NSGA-II multi-target optimization model, and taking maximization of an average power coefficient and minimization of a blade thrust standard deviation as targets; s6, substituting a function to obtain an optimal variable pitch control factor and an optimal pitch angle; and S7, the optimal pitch angle is converted into a variable pitch actuator instruction. The problems that an existing strategy is limited in partition, the wind direction influence is ignored, and optimal parameters for working condition adaptation are lacked are solved, the wind energy capture efficiency is improved, the load fluctuation is reduced, and the variable pitch control accuracy is improved.

The invention discloses a wind power variable pitch intelligent control method, and belongs to the field of wind power generation control. Aiming at the problems of wind speed abrupt change response lag, poor blade aging adaptation and low load control precision of existing variable pitch control, the method comprises the following steps: firstly, collecting real-time wind speed, blade strain, wind wheel rotating speed and blade historical data; predicting a short-term wind speed by using an improved ARIMA model, calculating a blade aging degree in combination with strain data, and determining a correction coefficient; then taking the predicted wind speed, the real-time strain and the correction coefficient as input, constructing a multi-target control model, and solving an optimal pitch angle through a particle swarm optimization algorithm; and finally, performing adjustment and performing real-time feedback and correction to form closed-loop control. The method can improve the variable pitch response speed, is adaptive to the full life cycle of the blade, balances the power generation efficiency and the unit safety, and is suitable for a multi-power-level wind turbine unit.

The invention relates to the technical field of data processing, and discloses a multi-source collaborative super-long wind power blade flexible variable pitch control method and system, and the method comprises the steps: constructing a response frequency band distribution matrix, effectively recognizing a frequency band overlapping interval caused by the distribution coupling of a modal frequency sequence and node coordinates in a flexible variable pitch blade, and obtaining a flexible variable pitch control result. The problem that in the prior art, control path frequency decoupling cannot be achieved under the condition of flexible response frequency band overlapping is solved, further, on the basis of an initial paddle angle path sequence, nonlinear projection analysis processing is introduced, a mapping drift vector is generated, and the path frequency decoupling effect is improved. The method is used for depicting a nonlinear projection drift trend generated by target propeller angle response in a variable-pitch control path, the problem of dynamic error accumulation caused by nonlinear projection drift of the variable-pitch path is solved, and through the two key steps, it is ensured that in an ultra-long flexible blade system, the nonlinear projection drift of the variable-pitch path is reduced. Cooperative execution of frequency domain mapping constraint and path offset correction can be achieved through variable pitch control.

The invention provides a controller for a wind turbine having three rotor blades, the controller being for controlling activation of individual pitch control of the rotor blades. The controller is configured to receive a flap load signal, from a flap loading sensor of each of the three rotor blades, indicative of flap loading on each of the respective rotor blades. The controller is configured to determine, based on the received flap load signals, a statistical dispersion parameter of flap loading for each of the rotor blades, the statistical dispersion parameters being indicative of a wind event in a wind field in which the wind turbine operates. The controller is configured to control activation of individual pitch control based on the respective statistical dispersion parameters.

The invention provides a floating fan strong wind resistance variable pitch control method based on an online optimization algorithm, and the method comprises the steps: describing main components of a floating fan structure, and building a high-fidelity nonlinear dynamic model of a floating wind generating set; carrying out linearization and discretization processing on the high-fidelity nonlinear dynamic model of the floating wind generating set near a cut-out wind speed working point, and giving a control-oriented linearization reduced-order model; constructing an augmented closed-loop control system model based on a standard proportional integral variable pitch control algorithm; performing residual error correction on the closed-loop control system model based on a Gaussian process; calculating a most unfavorable wind speed prediction value based on an online rolling optimization prediction control algorithm; calculating a minimum rotating speed reference derating value meeting security constraints; and calculating a final blade pitch angle instruction. According to the method, on the premise that the load does not exceed the safety upper limit under the strong wind working condition, the minimum necessary derating can be achieved through the online optimization algorithm, and the power generation capacity is kept to the maximum degree.

The invention relates to the technical field of wind power generation control, in particular to a variable pitch control method and system for a wind generating set, and the method comprises the steps: firstly obtaining a real-time operation data set which comprises a set state data unit and an environment parameter data unit and is provided with a timestamp mark, and carrying out the feature fusion processing of the real-time operation data set; a combined feature set reflecting the incidence relation between the blade stress state and the wind regime change is obtained, then a pre-trained pitch angle prediction model is called to predict the pitch angle adjustment amount of the combined feature set, and target pitch angle control parameters meeting the power generation efficiency and structural load balance are determined according to the prediction result; and finally, generating a variable pitch execution instruction containing timestamp alignment based on the target pitch angle control parameter, and sending the variable pitch execution instruction to a variable pitch control system, so that the pitch angle adjustment amount can be accurately predicted, the balance between the power generation efficiency and the structural load is realized, and the operation performance and reliability of the wind generating set are improved.

The invention relates to the technical field of wind power generation control, and discloses a model prediction variable pitch control method, system and equipment based on an LPV model, and a medium, and the method comprises the steps: building a full-range nonlinear variable pitch dynamic characteristic model of a wind turbine generator; through a gap measurement theory, representative working condition points are selected from a plurality of linearization models, and a linear variable parameter fan variable pitch model is constructed by taking the wind speed as a scheduling variable; and a multi-objective function is determined, a model prediction control problem is converted into a constrained quadratic programming problem for online solving, a control input quantity is calculated, and rolling optimization is carried out. According to the method, the pitch angle change is reduced, meanwhile, the loads of the blades and the hub are further reduced, the MPC control algorithm based on the LPV model can better reduce the power fluctuation under the step wind condition, and the tower footing load is reduced.

The invention provides a bending device and method for a coiled pipe of a heat exchanger, the coiled pipe of the heat exchanger is decomposed, and the whole structure is decomposed into a body spiral part and bent parts at the two ends; a spiral bending device is designed, and the spiral part of the coiled pipe body is bent; a pipe end bending device is designed, and the pipe end part of the coiled pipe is bent; the spiral bending device comprises a pipe bending unit, an inlet and outlet angle control unit and a screw pitch control unit, the pipe bending unit is used for bending the spiral part of the coiled pipe body, the inlet and outlet angle control unit is used for controlling the forming angles of the bent parts at the two ends of the coiled pipe, and the screw pitch control unit is used for controlling the screw pitch of the spiral part of the coiled pipe body. The bending device is adopted to solve the problems that heat exchanger coiled pipes of different specifications, pipe types and lengths are difficult to form, filler in an inner cavity is difficult to clean, the manufacturing test period of a special mold is long, and the forming precision of the coiled pipes is poor.

The invention discloses an active clearance control method and system for a wind turbine generator, and relates to the field of clearance control, and the method comprises the steps: obtaining a sound source signal, wind speed data and rotating speed data of fan blades, and determining the position of a sound source based on the sound source signal; determining a clearance distance based on the sound source position; when the wind speed data and the rotating speed data of the fan blades are both larger than a set threshold value, and the clearance distance is smaller than or equal to a set early warning threshold value, control parameters are optimized through an improved tribe competition and member cooperation algorithm, and the optimized control parameters are obtained; and variable pitch operation control is conducted based on the optimized control parameters, so that active control over the clearance distance is achieved. According to the method, the problem of lack of a corresponding effective active safety control strategy can be solved, and meanwhile, the problems of high cost, low precision, poor environmental adaptability, non-real-time performance and the like of a current wind turbine generator clearance detection mode are solved.

The invention belongs to the technical field of wind power generation control, and relates to a wind turbine variable pitch control method based on load prediction feedforward compensation, which comprises the following steps: firstly, analyzing the frequency spectrum of a wind speed and a load signal, and distinguishing the current interference as periodic load interference or instantaneous load interference according to discrete peak detection, a cross-power spectrum and an energy ratio; then analyzing the lateral energy ratio and multiband energy distribution of the wind wheel shaft to determine the direction of periodic load interference or the intensity change amplitude of instantaneous load interference; generating a corresponding feed-forward compensation signal; generating a synchronous reverse sine compensation signal for periodic load interference; for the instantaneous load interference, generating a filtering compensation signal in direct proportion to the intensity change amplitude of the instantaneous load interference; and finally, fusing the feedforward signal subjected to amplitude limiting and speed limiting processing with a power feedback signal, and outputting an integrated pitch angle instruction. According to the method, through distinguishing and corresponding compensation of the load types, the active inhibition capability of the variable pitch system on the complex load is improved.

The invention relates to the technical field of wind power management systems, and discloses an intelligent land wind power energy conservation and emission reduction management method and system. Comprising a data perception and acquisition module, a data transmission layer, a data processing and analysis layer, a power generation efficiency optimization module, an equipment health management module, a power grid coordination and energy storage optimization module, a carbon footprint tracking and reporting module and an application layer. The data sensing and collecting module collects wind speed, wind direction, temperature and air pressure data and generator rotating speed, gearbox temperature, blade angle and vibration frequency data in real time through a high-precision sensor, and low-delay data preprocessing is achieved through an edge calculation unit. In the invention, aiming at the delay problem of traditional yaw and variable pitch control, the system utilizes an intelligent algorithm to realize dynamic yaw and variable pitch control, and by accurately predicting the wind direction change and adjusting the fan direction and the blade angle in advance, the influence caused by complex wind conditions is effectively overcome, and the wind energy capture efficiency is greatly improved.

The embodiment of the invention provides a wind turbine generator blade clearance control system and method. The system comprises a strain measurement module which comprises a plurality of optical fiber strain sensors arranged on the inner surface of a wind turbine generator blade at intervals and is used for measuring the strain of the blade; the distance calculation module is used for calculating a predicted distance between the tip of the blade and the tower according to the strain of the blade, the current azimuth angle of the blade, the rotating speed of a wind wheel, the wind speed, the static distance between the tip of the blade and the tower, the length of the blade and the pitch angle of a cabin; the interference judgment module is used for judging whether the blade and the tower drum have interference risks or not according to the predicted distance; and the variable pitch control module is used for carrying out independent variable pitch control adjustment on the pitch angle of the blade when the interference risk exists between the blade and the tower drum. The embodiment of the invention is not influenced by environmental factors, and has the capability of protecting the blades from interference with the tower drum in all-weather operation; the independent variable pitch is used for achieving blade clearance protection control, and the generating capacity loss can be effectively reduced.

The invention belongs to the technical field of wind power control, and discloses a wind driven generator fixed time adaptive neural network variable pitch control method, which comprises the following steps: step 1, establishing a kinetic model of a wind driven generator, and initializing a system state and control parameters; 2, aiming at the wind driven generator system with external interference, designing a fixed time sliding mode surface based on a sliding mode thought; and step 3, designing a fixed-time adaptive neural network variable pitch controller. The method has the advantages that under the conditions that external interference exists in the wind driven generator and parameters are uncertain, rapid convergence of the rotor rotating speed tracking error within fixed time is achieved, and the convergence time does not depend on the initial state.

The invention discloses a large-scale wind turbine generator power load cooperative fault-tolerant control method. The method comprises the following steps: establishing a unit load and rotating speed control model considering a variable pitch actuator fault; according to the load and rotating speed control model, a fault-tolerant independent variable-pitch controller composed of a centralized variable-pitch ring, an independent variable-pitch ring and a fault-tolerant compensation ring is constructed for the three-blade variable-pitch actuator; and the fault-tolerant independent variable pitch controller inputs variable pitch given instructions corresponding to the blades to the corresponding variable pitch actuators, and the variable pitch actuators implement fault-tolerant variable pitch with the variable pitch given instructions as reference, so that power and load cooperative control under the fault working condition is achieved. According to the method, the optimization effect and the application capability boundary of pneumatic unbalanced load suppression of the wind wheel of the unit can be improved under the combined action condition of multi-source disturbance and variable-pitch actuator faults, meanwhile, the high stability of power output is guaranteed, and high-performance power-load cooperative control is achieved.

The invention discloses a wind turbine generator independent variable pitch control method embedded with wind speed self-adaptive predictive control, which belongs to the field of wind power, and comprises the following steps: establishing a mathematical model of a large wind turbine generator independent variable pitch system; establishing a mathematical model of a self-adaptive model prediction controller; establishing a mathematical model of a linear processor; and based on the established adaptive model prediction controller, taking a pitch angle signal as the input of a variable pitch system, and carrying out independent variable pitch control on the wind turbine generator. The linear processor is used for limiting the upper and lower output bounds of the signals, the variable pitch signals are dispersed into a plurality of signals to be output in one communication period, and the frequency transformation and amplitude fluctuation of the signals are reduced, so that the fatigue loss of a driving mechanism is reduced, the blade load reduction effect is improved, and the real-time change characteristic of the system is coped with through the wind speed self-adaption criterion. The problem of model mismatching caused by wind speed changes is solved, the performance of the controller is improved, and the method is suitable for systems with high control performance requirements and parameter changes.

The invention provides a jet pipe array missile pitching channel jet flow opening method, device and equipment and a medium. The method comprises the steps that corresponding total thrust is calculated according to pitching control torque needed by a missile; generating a plurality of spray pipe opening combinations capable of providing total thrust according to the thrust of a single spray pipe in the spray pipe array, and taking the spray pipe opening combinations as initial candidate modes; a sequential constraint rule from the middle to the two sides is applied to each nozzle opening combination in the initial candidate modes, and candidate modes conforming to the constraint rule are obtained; calculating a jet amplification factor of the candidate mode conforming to the constraint rule in the current flight state, and evaluating the influence degree of jet interference; the candidate modes with the jet amplification factors smaller than the preset minimum threshold value of the jet amplification factors and conforming to the constraint rule are removed, and the remaining candidate modes conforming to the constraint rule serve as jet opening modes, so that the problem that the control effect is poor due to poor control torque adjustability, control coupling, insufficient spray pipe utilization rate and jet interference influence is solved.

The invention discloses a yaw variable pitch control method, device and system based on wind regime prediction. The method comprises the steps that an original sensor data stream related to wind regime prediction is pulled from a message queue; pre-processing the original sensor data stream to obtain pre-processed first data; performing data windowing on the preprocessed first data; calculating a fuzzy entropy corresponding to the first data after windowing; selecting a corresponding reference model based on the fuzzy entropy to determine a predicted wind direction and a predicted wind speed; formulating a yaw control strategy according to the predicted wind direction, and formulating a variable pitch control strategy according to the predicted wind speed; and performing yaw control according to the yaw control strategy, and performing variable pitch control according to the variable pitch control strategy. According to the method, the wind direction and the wind speed are determined through wind regime prediction, the yaw control action is assisted, the control hysteresis is reduced, the system response speed is increased, and the accuracy of yaw and variable pitch control is improved.

According to the variable-pitch control optimization method for the offshore wind turbine generator, flapping matrixes of three blades are converted into d-axis and q-axis signal components under a rotating coordinate system through extended Collmann transformation in combination with a dynamic compensation angle technology, a compensation angle delta is dynamically calculated through a pneumatic unbalance factor (delta a) and a mass unbalance factor (delta m), and the compensation angle delta is calculated through a dynamic balance factor (delta m). And the adaptability of a load unbalance state is obviously improved. And then, a robust controller based on a product perturbation model is adopted to generate a control signal in a dq domain, and the robustness of the system to complex wind conditions (such as turbulence and wind shearing) on the sea is enhanced by minimizing weighted norms of a sensitivity function and a complementary sensitivity function and optimizing parameters by using a DK iterative algorithm. And finally, the control signals are mapped back to the independent control quantity of each blade through anti-Collman transformation, and the blade angle is adjusted in real time by combining a closed-loop P I execution system.

The invention discloses a wind turbine generator blade assembly dislocation guiding method, and relates to the technical field of wind turbine generator assembly.The wind turbine generator comprises a slewing bearing, a flange of a blade is connected with a bolt hole of the slewing bearing through a bolt, and the wind turbine generator blade assembly dislocation guiding method comprises the steps that the bolt is unscrewed, and the flange of the blade is connected with the bolt hole of the slewing bearing; the bolts and the bolt holes are kept in a connection state; obtaining the deviation displacement of the blade relative to the slewing bearing; generating a variable pitch control signal according to the deviation displacement by utilizing a control system; driving the blade to change the pitch according to the pitch control signal, enabling the blade to rotate relative to the slewing bearing by utilizing the inertia of the blade and compensating the deviation displacement so as to guide the blade; and tightening the bolt. The corresponding rotation amplitude is generated according to the deviation displacement, accurate guide of the blade is achieved, the guide accuracy of the blade is remarkably improved, connection between the blade and the slewing bearing does not need to be completely dismantled, special guide tools such as guide pins do not need to be used either, manpower and material resources are effectively saved, and the assembly cost is reduced.

The invention relates to activation of a pitch controller for controlling the pitch of a rotor blade of a wind turbine. The invention includes receiving a sensor signal from at least one sensor of the wind turbine, the sensor signal being indicative of oscillatory movement of a component of the wind turbine. The invention includes determining an amplitude of the oscillating motion of the component based on the received sensor signal, and determining a rate of change of the amplitude of the oscillating motion based on the determined amplitude. The invention includes controlling the activation of the pitch controller based on the determined rate of change of the amplitude of the oscillating motion.

The invention discloses an integrated driver special for wind power variable pitch based on silicon carbide. The integrated driver comprises a permanent magnet synchronous motor; the brake is arranged at the head of a rotating shaft of the permanent magnet synchronous motor; the encoder is arranged at the tail part of a rotating shaft of the permanent magnet synchronous motor; and the servo driver is arranged on a shell of the permanent magnet synchronous motor. The variable-pitch driver, the variable-pitch controller and the variable-pitch motor are integrated through integrated design, cables and connectors between modules can be eliminated, the connection failure risk caused by vibration / corrosion can be reduced, and therefore the failure rate is reduced. The size, the weight and the number of devices of the variable pitch system can be greatly reduced. Meanwhile, system wiring is simplified, and potential fault points are reduced.

The present invention discloses a method for judging and handling communication faults in a variable pitch control system of a fan. The heartbeat signal agreed upon by the variable pitch system and the main control system through the communication protocol is detected. If the heartbeat signal does not change within the preset time, it is judged that a communication fault occurs, and an emergency pitch reduction operation is executed. The present invention reliably ensures to avoid or reduce the influence of communication delay and communication interference on the heartbeat signal, improves the control accuracy of judging communication faults in the variable pitch control system of the fan, and improves the safety of the variable pitch control system of the fan.

The disclosure provides a pitch angle control method and device of a variable pitch wind turbine, and relates to the technical field of pitch control, which comprises the following steps: in response to detecting that the wind speed reaches a first wind speed, the pitch angle is controlled to keep the rotating speed of the wind turbine within a preset range; in response to determining that the wind turbine has been connected to the grid and detecting that the wind turbine is running at a first rotating speed, based on a preset first control strategy, the wind turbine is controlled to run at variable speed according to the current wind speed, so that the wind turbine reaches an optimal tip speed ratio; in response to determining that the output power of the wind turbine does not reach a rated output power, the pitch angle is controlled to control the wind turbine to run at the first rotating speed; and in response to determining that the wind turbine reaches the rated output power and the wind speed increases, the pitch angle is increased. Thus, the wind energy captured by the wind turbine can be controlled by adjusting the pitch angle, so as to improve the efficiency of the wind turbine and protect the wind turbine.