A multi-stage variable-diameter wind power generation device based on Venturi effect

Abstract

A kind of multistage variable-diameter micro-wind power generation device based on Venturi effect, including variable-diameter pipe, rotary support mechanism and power generation tower, the narrow end of variable-diameter pipe is connected on rotary support mechanism, rotary support mechanism is arranged on power generation tower;The power generation tower includes tower tube and generator, the lower part of tower tube is provided with diffusion section, generator is installed in tower tube, wind speed instrument is arranged on tower tube.Wind speed and wind direction are detected by wind speed instrument, rotary support mechanism is controlled to turn according to wind direction, so that the wide mouth of variable-diameter pipe always faces the direction of wind, wind force is increased by variable-diameter pipe, generator is driven to generate electricity, wind force is finally decelerated and discharged through diffusion section.This power generation device makes the wind channel narrow first and then expand, to generate variable pressure and variable speed function, to push the high-speed rotation of power generation blade, to improve the rated speed of generator, to reduce the starting torque, to increase the power and efficiency of generator, to ensure that the device always faces the direction of wind, to maximize the collection of wind energy, to improve the power generation.

Description

Technical Field

[0001] This utility model relates to a wind power generation device, and more particularly to a power generation device capable of concentrating wind and regulating light winds, belonging to the field of wind power generation technology. Background Technology

[0002] Wind energy, as a clean and renewable energy source, has been widely used in recent years. Micro-wind power generation utilizes wind energy to produce electricity, which is particularly important in areas with weak winds. However, one of the main challenges facing micro-wind power generation is the low efficiency of wind energy collection and conversion, and micro-wind power generation equipment typically requires relatively high wind speeds to produce effective power output.

[0003] Traditional micro-wind power generation systems struggle to produce sufficient electricity at low wind speeds. This is especially true in light wind conditions, where wind speeds are commonly between 2-3 meters per second, where power generation is poor. The fundamental reason is that the relatively low wind speeds in these conditions force the generator to operate at low speeds, making it difficult to drive the generator and generate electricity effectively. Summary of the Invention

[0004] This invention addresses the shortcomings of existing wind power generation equipment by providing a multi-stage variable diameter micro wind power generation device based on the Venturi effect that can generate electricity stably and efficiently at low wind speeds.

[0005] This utility model relates to a multi-stage variable-diameter micro-wind power generation device based on the Venturi effect, and adopts the following technical solution: The micro-wind power generation device includes a variable diameter pipe, a slewing support mechanism, and a power generation tower. The narrow end of the variable diameter pipe is connected to the slewing support mechanism, which is mounted on the power generation tower. The power generation tower includes a tower section and a generator. A diffuser section is provided at the bottom of the tower section, the generator is installed inside the tower section, and an anemometer is installed on the tower section.

[0006] One end of the reducing pipe is a horizontal wide air inlet, and the other end is a vertical narrow air outlet. The inner diameter of the wide air inlet is larger than the inner diameter of the narrow air outlet. An intermediate constriction is also provided between the wide air inlet and the narrow air outlet. The inner diameters of the wide air inlet, the intermediate constriction, and the narrow air outlet decrease sequentially, and the transition from the wide air inlet to the intermediate constriction and from the intermediate constriction to the narrow air outlet is gradual (through an arc transition).

[0007] The reducing pipe is equipped with a tail fin, which is opposite to the wide air inlet.

[0008] The slewing support mechanism includes a slewing support base and a servo motor. The slewing support base is mounted on the power generation tower and connected to the servo motor via a transmission mechanism. The servo motor is mounted on the power generation tower (specifically, the tower section). The inner hole of the slewing support base is coaxial with the inner hole of the power generation tower section, and their inner diameters are the same. The servo motor drives the slewing support base and the reducing pipe to rotate via the transmission mechanism. The transmission mechanism can be a gear drive, with a driving gear mounted on the servo motor shaft and a driven gear mounted on the slewing support base (the driven gear can be an integral structure with the slewing support base). Ball bearings are installed between the slewing support base and the power generation tower (specifically, the tower section) to allow the slewing support base to rotate flexibly. A protective cover is installed on the outer side of the slewing support base and is fixed to the power generation tower (specifically, the tower section). Both the servo motor and the anemometer are connected to a controller. The controller controls the operation of the servo motor based on the wind speed and direction monitored and measured by the anemometer.

[0009] The generator is a coreless disc generator.

[0010] The diffuser section is shaped like a downward-facing funnel, and air vents are provided on the outer side of the diffuser section to facilitate rapid air leakage.

[0011] Wind speed and direction are detected by an anemometer. Based on the wind direction, the slewing support mechanism is controlled to ensure that the wide inlet of the variable-diameter pipe always faces the direction of the wind. When the wind speed is less than the cut-out wind speed, the wind force increases the wind speed through the variable-diameter pipe, driving the generator to generate electricity and converting the captured wind energy into electrical energy. The wind is finally decelerated and discharged through the diffuser section, achieving efficient power generation. When the wind speed is greater than the cut-out wind speed, the direction of the variable-diameter pipe is adjusted by the slewing support mechanism so that the wide inlet faces away from the wind direction, stopping power generation.

[0012] This invention utilizes the Venturi effect to narrow and then widen the air duct, generating a variable voltage and speed function that drives the generator blades to rotate at high speed. This increases the rated speed of the generator, reduces the starting torque, and increases the generator power and efficiency. Combined with an anemometer and a slewing support motor, it automatically tracks the wind direction, ensuring that the device always faces the direction from which the wind is blowing, maximizing wind energy collection and increasing power generation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the multi-stage variable diameter micro wind power generation device based on the Venturi effect of this utility model.

[0014] Figure 2 yes Figure 1 The right view.

[0015] Figure 3 This is a schematic diagram of the slewing bearing mechanism in this utility model.

[0016] Figure 4 This is an equivalent cross-sectional view of the wide air inlet in this utility model.

[0017] Figure 5 This is a schematic diagram of the parameters in the multi-stage variable diameter micro wind power generation device based on the Venturi effect of this utility model.

[0018] Figure 6 This is a simulation diagram of the wind speed through a variable-diameter pipe.

[0019] In the diagram: 1. Reducer pipe; 2. Slewing support mechanism; 3. Power generation tower; 101. Wide air inlet; 102. Narrow air outlet; 103. Anemometer; 104. Tail fin; 105. Center taper. 201. Rotary support base; 202. Servo motor; 203. Sealing ring; 204. Protective cover; 301. Blade, 302. Coreless disc generator, 303. Diffuser section, 304. Vent, 305. Lower flange, 306. Tower, 307. Upper flange. Detailed Implementation

[0020] This invention relates to a multi-stage variable-diameter micro-wind power generation device based on the Venturi effect, such as... Figure 1 and Figure 2 As shown, it includes a reducing pipe 1, a slewing support mechanism 2, and a power generation tower 3. The reducing pipe 1 is connected to the slewing support mechanism 2, and the slewing support mechanism 2 is located at the upper end of the power generation tower 3.

[0021] The reducing pipe 1 is shaped like a reducing elbow, with a horizontal wide air inlet 101 and a vertical narrow air outlet 102. A horizontal intermediate constriction 105 is located between them. The inner diameters of the wide air inlet 101, the intermediate constriction 105, and the narrow air outlet 102 decrease sequentially, with gradual transitions from the wide air inlet 101 to the intermediate constriction 105 and from the intermediate constriction 105 to the narrow air outlet 102, all via an arc. A tail fin 104 is provided on the reducing pipe 1, opposite the wide air inlet 101, serving a balancing function. One end of the narrow air outlet 102 is connected to the slewing support 201 (see...). Figure 2 The entire reducing pipe 1 can rotate with the slewing support 201. Wind speed is monitored by an anemometer 103, which can be installed on the protective cover 204 or the tower 306.

[0022] Figure 6 The simulation results of wind speed in variable diameter pipe 1 are shown. Blue arrows represent low wind speed and red arrows represent high wind speed.

[0023] The structure of the slewing support mechanism 2 is as follows Figure 2As shown, the system includes a slewing support 201 and a servo motor 202. The slewing support 201 is stepped, with the upper outer diameter larger than the lower outer diameter, and has an inner hole. The upper part of the slewing support 201 rests on the upper flange 307 of the tower 306, and ball bearings are provided between them to allow the slewing support 201 to rotate flexibly. The lower part of the slewing support 201 extends into the tower 306, and a sealing ring 203 is provided between it and the inner wall of the tower 306. The servo motor 202 is mounted on the upper flange 307 of the tower 306. A transmission mechanism is provided between the servo motor 202 and the slewing support 201, which can be a gear drive. A driving gear is mounted on the shaft of the servo motor 202, and a driven gear is mounted on the slewing support 201. The driven gear can be an integral part of the slewing support 201. A protective cover 204 is provided on the outside of the slewing support 201, and the protective cover 204 can be fixed on the tower 306.

[0024] The power generation tower 3 includes a tower body 306 and coreless disc generators 302. The tower body 302 is a hollow structure with an inner bore that is cylindrical from top to bottom along the height direction. An upper flange 307 and a lower flange 305 are respectively installed at the upper and lower ends of the tower body 302. A diffuser section 303, shaped like a downward-facing trumpet, is located at the lower end of the tower body 306. Air vents 304 are provided on the outer side of the diffuser section 303 for rapid airflow; their shape and number are not limited. Multiple coreless disc generators 302 are installed inside the tower body 306, and can be evenly arranged vertically. The rotating shaft of each coreless disc generator 302 has blades 301, which are axial flow blades. The coreless disc generator 302 is existing technology. The coreless design avoids the problems of cogging torque and core eddy current losses in traditional generators during startup and low wind speed operation. The use of the coreless disc generator 302 further optimizes space utilization and improves power generation efficiency. This design not only effectively collects and converts wind energy, but also maintains high power generation efficiency under low wind speed conditions, bringing a new solution to the field of wind power generation.

[0025] The inner holes of the air outlet 102, the slewing support 201, and the tower 306 are coaxial and have the same inner diameter.

[0026] Both the anemometer 103 and the servo motor 202 are connected to the controller. Based on the wind speed and direction monitored and measured by the anemometer 205, the servo motor 202 drives the rotary support 201 to rotate. See also Figure 4Where V1 is the measured average wind speed (m / s) and α is the measured wind direction angle (degrees). The measured average wind speed (m / s) V1 is a vector. When the wind direction deflects by an angle α, the wind speed perpendicular to the section d of the air inlet 101 is V2 = V1 * cos(α). The angle α is collected by the anemometer 103 and provided to the controller. The controller controls the rotation speed of the servo motor 202 according to the angle α. The servo motor 202 rotates the variable diameter pipe 1 through the rotary support 201, adjusting the angle of the air inlet 101 so that the angle α is close to 0 degrees, thereby making the wind force perpendicular to the section d of the air inlet 101 and maximizing the utilization of wind energy.

[0027] The operation process of the above-mentioned micro-wind power generation device is as follows.

[0028] The entire device is fixed to the foundation via the lower flange 305 and bolts. A reducer 1 is used to increase the wind speed in light breezes, allowing even very weak winds to be effectively utilized. The reducer 1 essentially functions as a small "wind tunnel."

[0029] Initially, wind speed and direction are detected by an anemometer 205. Based on the wind direction, the servo motor 202 drives the slewing support 201 to rotate, ensuring that the wide air inlet 101 always faces the direction of the wind. Wind enters through the wide air inlet 101, its speed increases as it passes through the narrow air outlet 102, and it enters the tower 306, driving the blades 301 to rotate. This causes the coreless disc generator 302 to generate electricity, converting the captured wind energy into electrical energy. Finally, the wind speed is slowed by the diffuser section 303 and discharged through the air outlet 304, achieving efficient power generation.

[0030] Wind enters from the wide inlet 101 with a large inner diameter into a gradually narrowing middle section (from the outlet 102 to the upper end of the diffuser section 303), increasing the wind speed. It then enters the diffuser section 303, where the wind pressure decreases, stabilizing the airflow. An anemometer 205 measures the wind speed and direction. When the wind direction changes, the servo motor 202 drives the rotary support 201 to quickly rotate, ensuring that the wide inlet 101 of the variable diameter pipe 1 always faces the direction of the wind, maximizing power generation efficiency and output.

[0031] When the wind speed is less than the cut-out wind speed, the servo motor 203 operates as the wind direction changes, controlling the rotation of the slewing support 201 through the transmission mechanism. This adjusts the direction of the variable diameter pipe 1 in real time, keeping the air inlet 101 facing the wind, thus capturing continuous wind energy. When the wind speed is greater than the cut-out wind speed, the servo motor 202 operates to adjust the direction of the variable diameter pipe 1, making the air inlet 101 face away from the wind direction, thus stopping power generation.

[0032] According to the law of conservation of mass, for a steady-flowing incompressible fluid, the volume of fluid flowing through any cross-section of a pipe per unit time (i.e., the flow rate Q) is constant. See also... Figure 5, which can be expressed by the continuity equation formula: According to Q=A1*V1=A2*V2, it is derived that V2=A1 / A2*V1; When the cross-sectional area A1 of the air inlet wide port 101 is larger than the cross-sectional area A2 of the air outlet narrow port 102, A1 / A2>1, the wind speed V2 at the air outlet narrow port 102 is definitely greater than the wind speed V1 at the air inlet wide port 101. Let the area ratio coefficient K=A1 / A2, according to A1=(π*D1*D1) / 4, A2=(π*D2*D2) / 4, where π represents the pi, it is known that K=(D1*D1) / (D2*D2), thus obtaining: V2=K*V1; Further according to the wind energy formula: W=0.5*ρ*v^3*A, the wind energy W at the air outlet narrow port 102 is derived as W=0.5*ρ*(K*V1)^3*A2.

[0033] It can thus be concluded that: Wind energy W has a cubic relationship with velocity. When k doubles, the wind energy increases by 4 times. Therefore, the Venturi effect is utilized to increase the wind speed: adopting a design of collecting wind energy with a large diameter and increasing the wind speed with a small diameter, thereby increasing the supply of wind energy.

[0034] According to the wind pressure formula P=0.5*ρ*v^2*A, as well as A3=(π*D3*D3) / 4 and A4=(π*D4*D4) / 4, when D4>D3, P4<P3. When the area increases, the wind pressure will decrease, forming a low-pressure region, which further promotes the increase of wind speed and improves the wind energy.

[0035] Where: A1: Cross-sectional area of the air inlet wide port 101 (m 2 ); V1: Average wind speed at the air inlet wide port 101 (m / s); A2: Cross-sectional area of the air outlet narrow port 102 (m 2 ); V2: Average wind speed at the air outlet narrow port 102 (m / s); D1: Inner diameter of the air inlet wide port 101 (m); D2: Inner diameter of the air outlet narrow port 102 (m); D3: Outer diameter of the inner hole of the tower barrel 306 (m); D4: Outer diameter of the outlet (lower port) of the diffusion section 303 (m); A3: Cross-sectional area of the inner hole of the tower barrel 306 (m 2 ); V3: Average wind speed inside the tower barrel 306 (m / s); A4: Cross-sectional area of the outlet of the diffusion section 303 (m 2 ); V4: Average wind speed at the outlet of the diffusion section 303 (m / s); W: Wind energy (unit: w); ρ: Air density (unit: kg / m³); v: Wind speed (m / s); A: Cross-sectional area perpendicular to the wind speed (unit: m²). P: indicates wind pressure (unit: N / m²); P3: Indicates the air pressure inside tower 306 (unit: N / m²). P4: Indicates the outlet air pressure of diffuser section 303 (unit: N / m²).

[0036] With the wind speed remaining constant, this invention increases the wind speed V3 at the generator location, thereby improving power generation efficiency. Simultaneously, the clever use of the hollow tower structure reduces the overall system cost, resulting in significant economic benefits. For every 10% increase in wind speed V3, wind energy W increases by 33%. When wind speed V3 doubles, wind energy increases more than fourfold, and the same generator achieves more than four times the power output.

Claims

1. A multi-stage variable-diameter micro-wind power generation device based on the Venturi effect, characterized in that, It includes a reducing pipe, a slewing support mechanism, and a power generation tower. The narrow end of the reducing pipe is connected to the slewing support mechanism, which is mounted on the power generation tower. The power generation tower includes a tower section and a generator. A diffuser section is provided at the bottom of the tower section, the generator is installed inside the tower section, and an anemometer is installed on the tower section.

2. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 1, characterized in that, One end of the variable diameter pipe is a horizontal wide air inlet, and the other end is a vertical narrow air outlet. The inner diameter of the wide air inlet is larger than the inner diameter of the narrow air outlet.

3. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 2, characterized in that, An intermediate constriction is provided between the wide air inlet and the narrow air outlet. The inner diameter of the wide air inlet, the inner diameter of the intermediate constriction, and the inner diameter of the narrow air outlet decrease in sequence. The transition from the wide air inlet to the intermediate constriction and from the intermediate constriction to the narrow air outlet are all gradual.

4. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 1, characterized in that, The reducing pipe is equipped with a tail fin, which is opposite to the wide air inlet.

5. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 1, characterized in that, The slewing support mechanism includes a slewing support base and a servo motor. The slewing support base is installed on the power generation tower and is connected to the servo motor through a transmission mechanism. The servo motor is also installed on the power generation tower.

6. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 5, characterized in that, The inner hole of the slewing support is coaxial with the inner hole of the power generation tower, and their inner diameters are the same.

7. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 5, characterized in that, The transmission mechanism adopts gear transmission, with a driving gear installed on the shaft of the servo motor and a driven gear installed on the rotary support base; ball bearings are provided between the rotary support base and the power generation tower; a protective cover is provided on the outside of the rotary support base and the protective cover is fixed on the power generation tower.

8. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 5, characterized in that, Both the servo motor and the anemometer are connected to the controller.

9. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 1, characterized in that, The generator is a coreless disc generator.

10. The multi-stage variable-diameter micro-wind power generation device based on the Venturi effect according to claim 1, characterized in that, The diffuser section is shaped like a downward-facing funnel, and air vents are provided on the outer side of the diffuser section.

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