58results about How to "Improve wind energy utilization factor" patented technology

The invention relates to a wind-speed and rotating-speed sensorless full-wind-speed control strategy suitable for a small and medium sized fixed propeller-pitch variable speed permanent magnet synchronous wind generator set, and belongs to a master control system in the wind power generating control technology. The control strategy provided by the invention mainly comprises firstly, maximum power tracking control in low wind-speed area; secondly, constant power control in high wind-speed area (above rated wind speed); and thirdly, constant rotating-speed soft transition control between the maximum power tracking control and the constant power control. The realization of the control strategy is based on feedback of DC bus-bar voltage signals and DC bus-bar current signals; required DC bus-bar voltage reference value is given according to the change situations of the detected DC bus-bar current, so as to achieve the purpose that output power of the generator set is controlled by controlling the rotating speed of the generator set. Therefore, wind speed and rotational speed signals are not required to be detected in the control strategy, an expensive wind-speed and rotating-speed sensor can be saved, and accordingly, the control cost is greatly reduced, and the strategy has a good application prospect in the small and medium-sized wind generator sets below megawatt class.

The invention discloses a multi-wing collecting vane capable of utilizing wind power efficiently, comprising at least two wings and at least one zone formed between the adjacent wings. By designing the shape of each wing and the shape of the zone, the adjacent wings is enabled to generate a collecting effect on the fluid flowing through the zone between the adjacent wings, the zone is the space formed by the rear concave surface of front adjacent wings and the front convex surface of rear adjacent wings, and the rear concave surface and the front adjacent wings and the front convex surface of the rear adjacent wings are upward and front-biased; the relative direction of the adjacent wings is arranged for enhancing the collecting effect, the kinetic energy of the fluid flowing through the zone is increased, so the lifting force of the adjacent rings in the rear of the zone is improved, and the rotor power coefficient of the whole multi-wing collecting vane formed by the wings and the zones is accordingly improved. The multi-wing collecting vane capable of utilizing wind power efficiently makes full use of the Bernoulli effect and is more reasonable in design.

The invention provides a wind-turbine impeller provided with an air-jetting flap airfoil blade. On the airfoil tail edge of the blade or on the pressure face near the tail edge, for example, apart from the front edge at a distance of 80-100 percent of the airfoil string length, a row of air-jetting holes are drilled from the blade tip to the blade root or in a range with selected radius on the blades. The angle between the air-jetting direction and the airfoil string is controlled between 15 and 90 DEG. Using air-jetting to replace the function of the conventional flap improves the output power of the wind-turbine, lowers the starting wind-speed, enlarges the working range, as well as consumes no additional power, and lowers the electricity generating cost. The air-jetting is produced when the rotating centrifugal force of the blade sucks the air in front of a hollow wheel hub.

The present invention discloses one kind of bucket type wind force generator set with wide wind conveying mouth, and aims at provides one kind of wind force generator with simple structure, easy manufacture, very great power and very high efficiency, and capable of converging huge wind energy of wind with speed of 0.3-50 m/s and in the altitude of 0-500 m, converting the wind energy into mechanical energy effectively and generating AC power of 50 or 60 Hz.

The invention relates to the field of wind power generation with a variable pitch, in particular to a variable pitch control system used for controlling a blade and pitch angle of a wind turbine. The variable pitch control system comprises a detection unit, an independent variable pitch control unit and a variable pitch execution unit, wherein the detection unit is used for detecting the blade and pitch angle, a wind wheel rotating speed and a generator rotor speed; the independent variable pitch control unit is used for judging a relation between a wind speed and a cut-in wind speed according to the blade and pitch angle, wind wheel rotating speed and generator rotor speed signals detected by the detection unit, obtaining a pitch angle required by each blade according to a blade root load of each blade and outputting a corresponding control signal; and the variable pitch execution unit is used for independently and respectively regulating the pitch angle of each blade according to the control signal output by the independent variable pitch control unit. The pitch angle of each blade is controlled through an independent hydraulic system; and the independent pitch variable system has the advantages of simple structure, convenience for synchronous control and high control precision, quick response and big torque of the pitch angle and is capable of avoiding the defects, such as complex control mechanism, poor maintenance and the like of the current independent pitch variable system.

The invention discloses a method for designing a wind turbine airfoil by using a Bessel function curve. According to the method, the third-order Bessel function is adopted and can represent a section of curve through four control points only, and in addition, the starting point and the end point are fixed, so that only two control points are required to be changed for a section of the curve; each of an upper wing surface and a lower wing surface of the airfoil is represented by a section of curve, the starting points and the end points of the upper wing surface and the lower wing surface respectively coincide, and then the staring points and the end points are in smooth connection. According to the invention, the airfoil profile can be controlled more conveniently and effectively by using several points in space, so that optimization design time of the airfoil is shortened, and airfoil design efficiency is improved; the designed airfoil has an extremely high lift coefficient, so that chord length of a blade is reduced, and the material required by the blade is reduced; a higher lift-drag ratio is realized, so that the wind-power utilization coefficient is increased; the method can be popularized to design of wind turbine airfoils of different thicknesses, plane airfoils, turbine blade profiles and other complex curves and has a high social value and a good economic benefit.

The invention discloses a double-wind-wheel offshore floating type wind turbine generator. The double-wind-wheel offshore floating type wind turbine generator comprises a front wind wheel, a rear wind wheel, a rear hub, a cabin, a front hub, a tower drum, a floating body, a catenary and an anchoring device, wherein the front wind wheel is arranged in the upwind direction, the rear wind wheel is arranged in the downwind direction, the front wind wheel and the rear wind wheel are connected to the two ends of the cabin through the hubs, and the cabin, the tower drum and the floating body are sequentially connected from top to bottom; a yawing system is arranged at a flange plate between the cabin and the tower drum; blades of the front wind wheel and blades of the rear wind wheel are respectively connected to the front hub and the rear hub through flange plates; a variable pitch system is arranged at the flange plate, connected to the front hub, of each blade of the front wind wheel; a variable pitch system is arranged at the flange plate, connected to the rear hub, of each blade of the rear wind wheel; and the rear wind wheel can fully capture remaining wind energy of the front wind wheel, gradient utilization of the wind energy is achieved, the comprehensive wind energy utilization coefficient of the wind turbine generator is increased, wake flow effects are reduced, and the sea area utilization rate and the whole power generation efficiency of an offshore wind plant are improved.

The invention provides a rotation-speed control self-adaption optimizing method of a wind-power variable-speed constant-frequency unit. Effective information is screened out of wind-power variable-speed constant-frequency unit operation data, the unit optimal rotation-speed range operation knowledge is obtained through an inference machine driven by data in a PLC control system, and thus a rotation-speed-torque control curved line is adjusted automatically. The problem of optimal rotation-speed tacking deviation brought by pneumatic characteristic change caused by blade manufacturing, installation and aging, mechanical loss characteristic change of a transmission system and electric loss characteristic change of a power generator and a converter are solved, absorbed Cp of a variable-speed range impeller can be maximized, and the purpose of improving unit low-wind-speed power generation efficiency is achieved.

The invention discloses a ribbed and grooved type wind turbine blade and belongs to the technical field of wind power utilization. The surface of the wind turbine blade is formed by ten airfoil-shaped surface airfoil-shaped curves through continuous smooth transition. Each airfoil-shaped surface airfoil-shaped curve is composed of two parts, namely a leeside curve body and a windward side curve body, and each leeside curve body is provided with a downward-concave curve and an upward-convex curve. Ten airfoil-shaped surfaces are sequentially arranged in the blade unfolding direction, and grooved and ribbed structures are formed on the surface of the blade after smooth transition of the downward-concave curves and the upward-convex curves of the leeside curve bodies of the ten airfoil-shaped surfaces. The ribbed and grooved structures on the surface of the blade can effectively resist bending deformation caused by conventional vibration of the blade, and fatigue damage resistant capacity of the blade is improved obviously. Meanwhile, the grooved and ribbed structures on the surface of the blade do not enable pneumatic performance of the blade to be lowered, but the blade has good pneumatic performance.

The invention discloses a setover-type vertical-shaft wind machine capable of limiting rotating of blades, which comprises a tower frame and a wind wheel, wherein the wind wheel comprises a main shaft, lightweight blades, blade shaft brackets and blade shafts; the main shaft is mounted on the tower frame vertically, and can rotate freely; the blade shaft brackets are uniformly fixed on the main shaft radially; the blade shafts are vertically mounted at the both ends of the blade shaft brackets respectively; and the lightweight blades are fixedly mounted on the blade shafts, so that the lightweight blades can revolve relative to the blade shaft brackets, and the angle of revolution is 0-90 degrees. According to the wind machine, the solidity of the wind wheel is high; the wind blocking areas of the lightweight blades are increased; the solidity of the wind wheel is improved; the utilization factor of the wind energy is large; the rotating torque is increased; and power generating capacity is high. The wind wheel is small in starting wind speed; breeze power generating capacity is strong; the starting wind speed is low; when the resistance and the friction of a power generator are ignored, the starting wind speed is lower than 1m/s; the wind machine is suitable for wide regions; and the operating time proportion is high.

The invention relates to a self-protection wind-driven water lifting system with accelerating vanes. The self-protection wind-driven water lifting system comprises a water lifting mechanism directly driven by a wind power transmission mechanism and is characterized in that the cross sections of the vanes adopt NACA series wing sections, the streamline accelerating vanes are started at a low wind speed and output high torques, the vanes comprise low-speed vane tips and large-torsion vane roots and are divided into twenty cross sections from the vane roots to the vane tips for setting mounting angles, and the cross sections are in smooth transition with each other; a water outlet of a water pump of the water lifting mechanism is connected with a water-out pressure regulating cylinder of a hydraulic speed regulating mechanism. The problems of the traditional wind-driven water lifting system, such as large vane number and low wind energy utilizing rate are solved. The hydraulic speed regulating mechanism is driven to act through the skillful utilization of the water pressure of the water outlet of the water pump under large wind power, the wind power transmission mechanism is controlled to timely respond to yaw, and the purpose of automatically protecting system units is achieved. The self-protection wind-driven water lifting system is suitable for the farmland irrigating application of remote areas lack of electricity resources.

The invention relates to a vertical-axis wind turbine, specifically to a vertical-axis wind turbine in which a wind turbine impeller 10 is mounted within a volute 11; the exterior of an airflow channel inside the volute 11 is connected to a windward current collector 3 that can enlarge windward area, all the airflows of windward face are converged to the airflow channel inside the volute 11, the airflows in the airflow channel inside the volute 11 are used for driving all the blades of the wind turbine impeller 10 so that driving torque of the wind turbine is much higher than that of general vertical-axis wind turbine, and meanwhile, requirement of start-up wind speed of the wind turbine are greatly reduced, the start-up wind speed is lower than 2m/s and coefficient of utilization of wind energy is raised to above 0.8, thus realizing maximization of the efficiency of the wind turbine.

The invention discloses a method for improving wind power utilization of vertical axis wind turbine blade by using a guide strip technology. One guide strip is mounted on each of positions, which are located at 20%, 40%, 60% and 80% of the vertical axis wind turbine blade in a blade stretching direction. Height of the guide strips is 3% of blade chord length and thickness of the guide strips is 1% of the blade chord length. The guide strips extend to the blade tail edge from the blade front edge; and an offset distance front the front point positions of the front edges of the guide strips to final points of the tail edges of the guide strips is 6% of the blade chord length. The method has the effects and beneficial effects that: a flow-through path of airflow of the wind turbine blade is controlled by adopting the blade guide strip technology, so that angles that the airflow enters and leaves the blade are changed, thereby increasing lifting force of the blade and increasing tangential force of the blade simultaneously. The method has the advantages of reducing starting wind velocity of a fan, improving a wind energy utilization coefficient, and the like.

The invention discloses a variable-pitch net-shaped stay wire wind wheel, and belongs to the technical field of new energy. The variable-pitch net-shaped stay wire wind wheel comprises a wheel hub (1), a wheel rim (8), blades (3) and stay wire cables (2), wherein the wheel hub (1) and the wheel rim (8) are fixedly connected into a whole through the stay wire cables (2), and are tensioned through wire cable tensioners, and the stay wire cables (2) longitudinally penetrate through the blades (3). The variable-pitch net-shaped stay wire wind wheel is characterized in that the inner end and the outer end of each blade (3) are connected with blade variable-pitch devices, an outer supporting plate at the outer end of each blade (3) is hinged to each outer connecting line (5), each outer connecting line (5) is connected with one end of each outer rotating plate beside the outer connecting line, the other end of each outer rotating plate is connected with an outer backstay cable (4), a middle shaft of each outer rotating plate is hinged to an outer support fixed to the wheel rim (8), an inner supporting plate at the inner end of each blade (3) is hinged to an inner connecting line (7), each inner connecting line (7) is connected with one end of an inner rotating plate, and the other end of each inner rotating plate is connected with an inner backstay cable. According to the variable-pitch net-shaped stay wire wind wheel, variable-pitch stability of the blades is good, the helical face of a windward side of each blade is small in change, the wind power utilization coefficient is greatly improved, cost is greatly reduced, and the defects of a three-blade wind wheel and the defects of an existing stay wire wind wheel are overcome.

The invention discloses a thickened wind turbine blade with high pneumatic performance, which belongs to the technical field of wind energy utilization. A three-dimensional structure on the surface of a blade wing-shaped part is generated by continuous and smooth transition of ten wing-shaped surface wing-type curves; each wing-shaped surface wing-type curve consists of a leeward surface curve and a windward surface curve respectively; an original point of a coordinate system is defined as the front edge point of a first wing-shaped surface wing-type curve; the leafing direction of the blade is defined as the positive direction of an axis Z; the direction of a wind wheel shaft is defined as the direction of an axis Y; another direction which is vertical to the directions of the axis Z and the axis Y is defined as the direction of an axis X; ten wing-shaped surfaces are parallel to a plane X0Y respectively, and are arranged in sequence along the positive direction of the axis Z; the ten wing-shaped surfaces rotate by certain angles by taking the front edge points in a plane which crosses respective front edge points and is vertical to the axis Z. According to the thickened wind turbine blade, the front and back edge points of blade wings are thickened, so that the blade has high bending resistance and fatigue damage resistance on the premise of ensuring high pneumatic performance; meanwhile, the blade has the characteristics of low starting air speed and low working noise.

The invention discloses a lift type blade airfoil for a vertical-axis wind turbine generator system and aims to improve the shortcomings of higher sensitivity of a maximum lift coefficient to leading edge roughness, poor stalling characteristics, lower maximum lift-to-drag ratio, low capacity for work and the like of a symmetric airfoil. According to the lift type blade airfoil, (1) the maximum camber 19.8 percent of the blade airfoil is at the 30.4 percent airfoil chord; (2) the maximum curvature 0.59 percent of the blade airfoil is at the 22.3 percent airfoil chord; (3) the leading edge radius of the blade airfoil is 1.8523 percent; (4) the trailing edge thickness of the blade airfoil is 0.15 percent. The lift type blade airfoil has the benefits that the attack angle range between the Reynolds number of 150,000 to 700,000 is wider, and the trailing edge is free of laminar separation, so that noise is reduced; stalling occurs after a high attack angle, and the lift coefficient is finitely reduced after stalling, so that the sensitivity of the maximum lift coefficient to the leading edge roughness is reduced, the overall wind energy utilization coefficient is improved, and the theoretical wind energy utilization efficiency reaches 0.48; in addition, the airfoil is thickened, so that structural strength is strengthened.

The invention discloses a wind power generator and particularly discloses a sail type vertical axis wind power generator. The sail type vertical axis wind power generator is characterized in that a sail and a sail hoisting device are mounted on the periphery of a wind wheel; a mast centre O1 of the sail is revolved around a wind wheel center O; at the same time, the sail rotates around the mast centre O1 of the sail along the opposite direction; and a sheering device is mounted on the wind wheel. The sail type vertical axis wind power generator does no negative work at the direction against the wind so as to increase the rotor power coefficients. The theory numerical value thereof breaks through the Betz limit. The wind power generator is low in starting speed and high in cut-out speed, has long working time and high resource use ratio, and is mainly constructed on the ground in order to conveniently construct and maintain. The wind wheel of the wind power generator has no yawing force and utilizes the shifting by hoisting the sail.