9 results about "Tower shadow" patented technology

This invention belongs to the field of wind power generation technology and discloses a biomimetic tower for a wind turbine and a wind turbine generator. The biomimetic tower for the wind turbine generator includes a tower body and a biomimetic inner rib structure. The diameter of the tower body gradually decreases from bottom to top. The biomimetic inner rib structure is connected to the inner wall of the tower body. The biomimetic inner rib structure includes multiple circumferential inner ribs, multiple axial inner ribs, and double diagonal stiffening ribs. The multiple circumferential inner ribs and multiple axial inner ribs enclose multiple lattice units. The double diagonal stiffening ribs include multiple first stiffening ribs and multiple second stiffening ribs. The multiple first stiffening ribs and multiple second stiffening ribs are arranged at an angle within the lattice units and are connected to the sides of the lattice units. This biomimetic tower for the wind turbine generator has better overall stability, can control the vibration amplitude at the top of the tower, and can improve buckling resistance, fatigue resistance, and vibration reduction performance without changing the outer surface shape and near-field flow boundary, while avoiding adverse effects on tower shadow effect and wake characteristics.

This application discloses an equivalent wind speed modeling method and related apparatus that considers wind shear and tower shadow effects. The method introduces frequency characteristic correction based on the first equivalent wind speed considering wind shear and the second equivalent wind speed considering tower shadow effects, which effectively improves the strong dependence of the equivalent wind speed model on model parameters. Then, the final equivalent improved wind speed is calculated based on the corrected wind speed and the inflow wind speed, which improves the accuracy of the equivalent wind speed model in characterizing the impact of wind shear and tower shadow effects on unit power under non-precise parameter conditions, and helps to promote wind power technology research oriented towards electrical characteristic analysis and control.

The invention discloses a downwind type small wind driven generator turbine which comprises a rotor blade body axially swept back from a blade root to a blade tip, the front edge of the blade is provided with a bionic nodule structure changing in a sine rule, and the rear edge of the blade is provided with a sawtooth-shaped corrugated structure; the blades and the hub are connected to form a wind turbine rotor, the rotor is located on the downwind side of the tower, wind flow firstly passes through the tower and then acts on the rotor blades, the downwind layout enables the blades to be capable of natural feathering under the action of wind loads, therefore, dynamic load impact on the tower is reduced, and the yaw system structure is simplified. The tower shadow effect can be remarkably relieved through the whole sweepback type blades, and aerodynamic noise is reduced; the front edge nodules of the blades are bionic to fin limbs of the seat head whale, so that the lift-drag ratio can be effectively increased, broadband noise is reduced, and violent fluctuation of power and load is inhibited; sawtooth ripples on the rear edge of the blade imitate a comb-shaped structure on the rear edge of the flying feather of the owl, so that vortex shedding frequency concentration can be inhibited, and high-frequency noise can be remarkably reduced.

The invention relates to the technical field of remote sensing image geometric inversion, in particular to a shadow geometric constraint-based fan three-dimensional information reconstruction method, which comprises the following steps of: firstly, acquiring a remote sensing image containing a target fan, identifying a tower drum shadow and a corresponding fan blade shadow of each fan, and extracting a shadow vector; further establishing a fan coordinate system, constructing a conversion relation between the fan coordinate system and a remote sensing image coordinate system, and constructing a shadow geometric constraint model according to a projection relation of a space vector projected to a ground plane along a sunlight direction under the conditions that three fan blades mutually form an angle of 120 degrees and a solar altitude angle is lacked; on the basis, a nonlinear constraint equation set containing the fan tower height, the fan blade radius, the fan azimuth angle and the sun projection direction parameters is established, the fan tower height and the fan blade radius are obtained through optimization solving, and fan three-dimensional information reconstruction is achieved. According to the method, the solar altitude does not need to be known, fan structure parameter inversion can be completed only by depending on a single remote sensing image, and the method has the advantages of being high in calculation precision and high in applicability.

This application belongs to the field of wind power generation technology, and specifically discloses a method for analyzing the mechanical-electrical coupling characteristics of large wind turbine units. The method includes: constructing a nonlinear time-varying model of the wind turbine unit's machine-side system, which includes mechanical and electrical subsystems, based on the wind turbine unit's mechanical parameters, electrical parameters, control parameters, operating data, and periodic aerodynamic loads caused by wind shear and tower shadow effects; performing time-domain simulation on the nonlinear time-varying model to obtain the periodic steady-state trajectory of the machine-side system under set operating conditions; linearizing the nonlinear time-varying model based on the periodic steady-state trajectory to establish a linear periodic time-varying state-space model, and calculating the state transition matrix within one fundamental period; calculating the Floquet characteristic index of the wind turbine unit using Floquet-Lyapunov theory based on the state transition matrix, and determining the small-disturbance stability of the machine-side system based on the real part of the Floquet characteristic index.

The present application relates to the technical field of remote sensing image geometric inversion, in particular to a fan three-dimensional information reconstruction method based on shadow geometric constraint, which comprises the following steps: first, obtaining remote sensing images containing target fans, identifying the tower shadow and corresponding blade shadow of each fan and extracting shadow vectors; further, establishing a fan coordinate system and constructing the conversion relationship between the fan coordinate system and the remote sensing image coordinate system; under the condition that three blades are mutually 120 degrees and the solar elevation angle is missing, constructing a shadow geometric constraint model according to the projection relationship of spatial vectors along the sunlight direction to the ground plane; on this basis, establishing a nonlinear constraint equation group containing the fan tower height, blade radius, fan azimuth angle and solar projection direction parameters, obtaining the fan tower height and blade radius through optimization solution, and realizing the three-dimensional information reconstruction of the fan. The present application does not need to know the solar elevation angle, and can complete the fan structure parameter inversion only by relying on a single remote sensing image, and has the characteristics of high calculation precision and strong applicability.

This application discloses a method, apparatus, electronic device, and medium for determining wind speed and direction considering the tower shadow effect of a wind measuring tower. The method may include: identifying two sets of wind measuring devices A and B at the same height and collecting initial data from A and B respectively; dividing the current area into multiple sectors, determining the degree of influence of the tower shadow effect on wind speed in each sector, and then evaluating the accuracy of the wind speed measurements; calculating the median ratio of the wind speeds of A and B to determine the degree of influence of the tower shadow effect on wind speed in each sector, and then determining the wind direction in each sector. This invention provides corresponding wind direction determination strategies for sectors with different wind directions, enabling wind direction determination with a wind measuring tower equipped with dual wind direction sensors, thus providing stable and reliable wind direction data.

A wind farm induced sub-synchronous oscillation and evolution rule analysis method, comprising: according to the topology and physical parameters of the wind turbine, a single-machine multi-physical coupling model containing an aerodynamic system, a mechanical system, an electrical system and a control system is established, the propagation path and frequency coupling characteristics of the equivalent wind speed low-frequency oscillation caused by the wind shear effect and the tower shadow effect to the electric energy oscillation are revealed;According to the physical state and spatial layout among different wind turbines, a wind farm aggregation model is established;The multi-machine disturbance coupling modeling is completed by combining the single-machine model and the aggregation model, and the evolution rule of single-machine sub-synchronous oscillation to wind farm sub-synchronous oscillation and its time domain and frequency domain characteristics are obtained.The present application provides technical support for the identification and prevention and control of new energy grid oscillation type, and can be used to ensure the safe and stable operation of power grid.