A wind energy collection device and method for low wind speed

Abstract

The present invention discloses a wind energy collection device and method for low wind speed, belonging to the technical field of wind energy utilization. It includes a bracket, a spring, a dielectric elastomer film, a U-shaped connecting frame and a vibrator; the bracket plays a supporting and fixing role, and the U-shaped connecting frame is hinged with the bracket so that it can swing left and right around the straight line where the hinge point is located; a vertically arranged vibrator is installed on one side of the hinge point of the U-shaped connecting frame, and a vertical rod parallel to the vibrator is installed on the other side; a spring and a vibrating rod perpendicular to the plane where the U-shaped connecting frame is located are arranged on the vertical rod, and the two ends of the spring are fixed by the bracket, and the middle part of the spring is connected to the vertical rod. A pair of dielectric elastomer films are arranged on both sides of the vibrating rod, and a distance is left between the end of the vibrating rod and the dielectric elastomer film; electrodes are arranged on the two end surfaces of the dielectric elastomer film and connected to the electric energy collection circuit, and the capacitance changes with the stretching and compression of the dielectric elastomer film, thereby changing the internal connection relationship of the electric energy collection circuit to generate and collect electric energy.

Description

Technical Field

[0001] The present invention relates to the technical field of wind energy utilization, and in particular to a wind energy collection device and method for low wind speeds. Background Art

[0002] Energy is the cornerstone of human survival and development. The rapid development of modern human society mainly relies on traditional fossil energy, which has also caused a series of environmental and health problems, threatening the sustainable and healthy development of society. The development and utilization of clean renewable energy provides new ideas and options for human development, is one of the effective ways to solve existing environmental and development problems, and is the prerequisite for achieving sustainable and healthy social development.

[0003] At present, the main renewable energy power generation technologies are: solar power generation, hydropower generation, wind power generation and biomass power generation. As one of the important energy sources given by nature, wind energy is a widely recognized new energy source. The theoretical reserves of wind energy resources in my country are rich, and the potential for development is huge. However, my country's wind power generation is mainly concentrated in high wind speed areas with rich wind energy resources such as the three northern regions and the southeast coast, while wind energy resources in low wind speed areas are widely distributed in my country, accounting for about 68% of the country's available wind energy area. However, wind energy resources in low wind speed areas have hardly been developed and utilized, which is undoubtedly a great waste of wind energy resources. Therefore, exploratory research on low wind speed wind energy collection devices is of great significance to the development of my country's wind energy industry and energy conservation and emission reduction.

[0004] Dielectric elastomer (DE) is a new type of textile material that can deform and convert energy under the stimulation of an external electric field. It belongs to electroactive polymers. Using dielectric elastomers to generate electricity has the characteristics of large deformation, high energy density, high efficiency and low cost. The dielectric elastomer generator (DEG) is based on the principle of variable capacitance. Under the action of external mechanical force, the DE film deforms and converts mechanical energy into electrical energy. However, there are few cases of dielectric elastomers in wind energy development. This is mainly because the DE film cannot be separated from an external high-voltage power supply, and secondly, there are problems with the utilization and storage of the obtained electrical energy. Summary of the invention

[0005] In order to overcome the above technical problems, the present invention discloses a wind energy collection device and method for low wind speeds, which improves the utilization rate of wind energy resources in low wind speed areas.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A wind energy collection device for low wind speeds, comprising a bracket, a spring, a dielectric elastomer film, a U-shaped connecting frame and a vibrator;

[0008] The bracket plays a supporting and fixing role. The U-shaped connecting frame is hinged to the bracket, so that the U-shaped connecting frame can swing left and right around the straight line where the hinge point is located; a vertically arranged vibrator is installed on one side of the hinge point of the U-shaped connecting frame, and a vertical rod parallel to the vibrator is installed on the other side; the vertical rod is provided with a spring and a vibration rod perpendicular to the plane where the U-shaped connecting frame is located, the two ends of the spring are fixed by the bracket, the middle part of the spring is connected to the vertical rod, and a pair of dielectric elastomer films are provided on both sides of the vibration rod, and a distance is left between the end of the vibration rod and the dielectric elastomer film.

[0009] As a preferred embodiment of the present invention, a rubber ring is provided at the end of the vibrating rod.

[0010] As a preferred embodiment of the present invention, the dielectric elastomer film is fixed on both sides of the vibration rod through a pair of mounting plates, and the plane where the dielectric elastomer film is located is perpendicular to the motion arcs at both ends of the vibration rod.

[0011] As a preferred embodiment of the present invention, electrodes are provided on both end surfaces of the dielectric elastomer film and connected to an electric energy collection circuit. As the dielectric elastomer film is stretched and compressed, the capacitance changes, thereby changing the internal connection relationship of the electric energy collection circuit to generate and collect electric energy.

[0012] As a preferred embodiment of the present invention, the electric energy collection circuit includes a second-order self-bias circuit, an electret electrostatic voltage source, a rectifier bridge and a voltage-stabilizing diode; the electrodes on both sides of the dielectric elastomer film, the second-order self-bias circuit, the voltage-stabilizing diode and the rectifier bridge are respectively connected in parallel with the electret electrostatic voltage source.

[0013] As a preferred embodiment of the present invention, the second-order self-bias circuit includes a diode D1, a diode D2, a diode D3, a diode D4, a diode D5 and an internal capacitor, wherein the internal capacitor includes a first capacitor and a third capacitor with a capacitance value of C, and a second capacitor and a fourth capacitor with a capacitance value of C / 2;

[0014] The five diodes are connected in series and connected to an electret electrostatic voltage source, and the cathode of the series-connected diode D1 is connected to the anode of the electret electrostatic voltage source, and the anode of the diode D5 is connected to the cathode of the electret electrostatic voltage source; one end of the first capacitor is connected to the anode of the diode D2, and the other end is connected to the anode of the electret electrostatic voltage source; one end of the second capacitor is connected to the cathode of the diode D2, and the other end is connected to the cathode of the electret electrostatic voltage source; one end of the third capacitor is connected to the anode of the diode D4, and the other end is connected to the cathode of the electret electrostatic voltage source; one end of the fourth capacitor is connected to the cathode of the diode D4, and the other end is connected to the cathode of the electret electrostatic voltage source.

[0015] As a preferred embodiment of the present invention, the low wind speed range is 1-4 m / s, and more preferably 1.5-3 m / s.

[0016] As a preferred embodiment of the present invention, the vibrator is a square column or a trapezoidal column.

[0017] The above-mentioned wind energy collection method for the wind energy collection device at low wind speed comprises:

[0018] The electrodes on both sides of a pair of dielectric elastomer films are respectively connected to an electric energy collection circuit. In an initial state, an electret electrostatic voltage source injects charges into the second-order self-bias circuit and the dielectric elastomer film, so that both ends of the dielectric elastomer film and both ends of the second-order self-bias circuit have equal initial low voltages.

[0019] When wind blows through the vibrator, the vibrator vibrates, driving the U-shaped connecting frame to swing left and right. Driven by the U-shaped connecting frame and the action of the spring, the two ends of the vibrating rod continuously hit the dielectric elastomer films on both sides, causing the impacted dielectric elastomer films to continuously produce tensile-compression deformation, resulting in a change in capacitance. Among them, when the dielectric elastomer film is hit by the vibrating rod, the voltage on both sides of the dielectric elastomer film decreases, and the dielectric elastomer film is charged by the second-order self-bias circuit; when the dielectric elastomer film is released, the voltage on both sides of the dielectric elastomer film increases, and the dielectric elastomer film is charged to the second-order self-bias circuit.

[0020] Furthermore, the alternating current on both sides of the dielectric elastomer film is converted into direct current through a rectifier bridge for supplying power to the outside.

[0021] Compared with the prior art, the advantages of the present invention are:

[0022] (1) The present invention drives the U-shaped connecting frame to swing left and right through the vibration of the vibrator, and then under the action of the spring, the two ends of the vibrating rod continuously hit the dielectric elastomer film. It is particularly suitable for converting wind energy into electrical energy under low wind speed conditions. The design of dual dielectric elastomer films can generate double electrical energy at the same time.

[0023] (2) The present invention can adjust the positions of the two hinge points in the U-shaped connecting frame according to actual conditions, thereby changing the amplitude of left and right swinging, so that the dielectric elastomer film works in the best state.

[0024] (3) In the process of converting wind energy into electrical energy, the electrons move back and forth between the dielectric elastomer capacitor and the second-order self-bias circuit, which is different from the DC working mode of the traditional external power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of a wind energy collection device for low wind speeds shown in an embodiment of the present invention;

[0026] Figure 2 is a right side view of a wind energy collection device for low wind speeds shown in an embodiment of the present invention;

[0027] Figure 3 is a schematic diagram of the structure of an electric energy collection circuit shown in an embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of two working states of the second-order self-bias circuit SPC;

[0029] Figure 5 It is the test result of the wind energy collection device at low wind speed (2.0m / s);

[0030] Figure 6 It is the test result of the wind energy collection device in the low wind speed range (1.5-4m / s);

[0031] Figure 7 It is a schematic diagram of charging a 40mAh lithium battery using a wind energy collection device;

[0032] In the figure, 1- bracket, 2- spring, 3- dielectric elastomer film, 4- U-shaped connecting frame, 5- vibrator, 6- vibrating rod. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings.

[0034] like Figure 1-2 As shown, a wind energy collection device for low wind speeds converts wind energy into electrical energy based on the principle of vortex-induced vibration wind power generator, which mainly includes: a bracket 1, a spring 2, a dielectric elastomer film 3, a U-shaped connecting frame 4 and a vibrator 5.

[0035] In this embodiment, the bracket is a rectangular frame structure built with aluminum profiles, which plays a supporting and fixing role; the U-shaped connecting frame includes a pair of horizontal bars and a vertical bar, the pair of horizontal bars are parallel and equal in length, the vertical bar is connected to one end of the same side of the two horizontal bars, and the vibrator is connected to the other end of the same side of the two horizontal bars; the middle part of the pair of horizontal bars is hinged to the bracket, so that the U-shaped connecting frame can swing left and right around the straight line where the two hinge points are located; in this embodiment, the cross-section of the vibrator is rectangular or trapezoidal, preferably an isosceles trapezoid, and the long base of the isosceles trapezoid faces the windward side.

[0036] The vertical rod is provided with a spring and a vibrating rod perpendicular to the plane where the U-shaped connecting frame is located. The two ends of the spring are fixed by brackets, the middle of the spring is connected to the vertical rod, and a pair of dielectric elastomer films are provided on both sides of the vibrating rod, and a distance is left between the end of the vibrating rod and the dielectric elastomer film.

[0037] Electrodes are arranged on both end surfaces of the dielectric elastomer film and connected to an electric energy collection circuit. As the dielectric elastomer film is stretched and compressed, capacitance changes, thereby changing the internal connection relationship of the electric energy collection circuit to generate and collect electric energy.

[0038] Figure 1 The working principle of the wind energy collection device shown for low wind speeds is:

[0039] When wind blows through the vibrator, the vibrator vibrates, driving the U-shaped connecting frame to swing left and right. Driven by the U-shaped connecting frame and the action of the spring, the two ends of the vibrating rod continuously hit the dielectric elastomer film, causing the film to continuously produce tensile-compression deformation, resulting in a change in capacitance. In the energy collection circuit, at wind speeds above 1.5m / s, a single dielectric elastomer film can generate several thousand volts of voltage and tens of microamperes of current without the need for an external high-voltage power supply, which can greatly utilize wind energy resources in low wind speed areas.

[0040] Figure 3 The schematic diagram of the structure of an electric energy collection circuit used in an embodiment of the present invention is shown, and the electric energy collection circuit includes a second-order self-biasing circuit (Self-priming circuit, SPC), an electret electrostatic voltage source (Electrete electrostatic voltage source, EEVS), a rectifier bridge, a voltage regulator diode, etc. The electrodes on both sides of the dielectric elastomer film, the second-order self-biasing circuit, the voltage regulator diode, and the rectifier bridge are respectively connected in parallel with the electret electrostatic voltage source, and the dielectric elastomer film and the electrodes on both sides thereof are equivalent to the dielectric elastomer capacitance (Dielectric Elastomer capacitance, DEC). Because excessive voltage will break down the DEC, the voltage regulator diodes arranged on both sides make the DEG stable at a maximum of about 3500V when working, and the rectifier bridge converts the alternating current generated by the DEG into direct current, which can be used to directly power batteries or sensors.

[0041] The second-order self-bias circuit SPC comprises diodes D1, D2, D3, D4, and D5, a pair of capacitors C, and a pair of capacitors C / 2. The five diodes are connected in series to the positive and negative electrodes of the electret electrostatic voltage source, and the negative electrode of the series-connected diode D1 is connected to the positive electrode of the electret electrostatic voltage source, and the positive electrode of the diode D5 is connected to the negative electrode of the electret electrostatic voltage source; one end of the first capacitor with a capacitance value of C is connected to the positive electrode of D2, and the other end is connected to the positive electrode of the electret electrostatic voltage source; one end of the second capacitor with a capacitance value of C / 2 is connected to the negative electrode of D2, and the other end is connected to the negative electrode of the electret electrostatic voltage source; one end of the third capacitor with a capacitance value of C is connected to the positive electrode of D4, and the other end is connected to the positive electrode of the electret electrostatic voltage source; one end of the fourth capacitor with a capacitance value of C / 2 is connected to the negative electrode of D4, and the other end is connected to the negative electrode of the electret electrostatic voltage source.

[0042] The working principle of the energy collection circuit is as follows: At the beginning, EEVS injects charge into SPC and DEC through the rectifier bridge and the voltage regulator diode D2, so that DEC has an initial low voltage of more than ten volts at both ends. When DEC is deformed, the capacitance of DEC will change. Because DEC and SPC are in parallel, the initial voltages at both ends are equal. Then, during the stretching-relaxation process of DEC, a voltage difference exists between DEC and SPC.

[0043] The second-order self-bias circuit SPC has two working states, such as Figure 4 As shown in the left figure, when the voltage value VD of DEC is greater than the sum of the voltage value VC of the first capacitor / fourth capacitor in SPC and the voltage value VC / 2 of the third capacitor / second capacitor, diodes D2 and D4 are turned on, and D1, D3, and D5 are disconnected, forming two capacitors in series, and current flows from DEC to SPC.

[0044] like Figure 4 As shown in the right figure, when the voltage value VD of DEC is less than VC, diodes D2 and D4 are disconnected, D1, D3, and D5 are turned on, and the current flows from SPC to DEC.

[0045] If the voltage on both sides of DEC is between Figure 4 When the voltage of the SPC circuit is between the two working states, DEC is in the reverse cut-off state and does not generate current.

[0046] In the present invention, when DEC is hit by the vibrating rod, the capacitance value of the dielectric elastomer capacitor increases, its voltage decreases, and SPC charges DEC; when DEC is released, the capacitance value of the dielectric elastomer capacitor decreases, its voltage increases, and DEC charges SPC.

[0047] In this embodiment, the electrodes on both sides of the dielectric elastomer film play a conductive role. The electrodes are not limited to conductive pastes, such as conductive gel, ion elastomer, gold foil, etc. The electrodes do not affect the stretchability of the dielectric elastomer film.

[0048] The wind energy collection device in this embodiment was placed under low wind speed (2.0 m / s) for testing, and the following results were obtained: Figure 5 The results shown in the figure show that it stably generates a voltage close to 4kV and a current value of about 50μA. The test is continued at a wind speed of 1.5-4m / s, and the following is obtained: Figure 6 The test results shown in the figure show that as the wind speed increases, the current generated in the wind speed range of 1.5-3m / s shows an upward trend. Above 3m / s, considering environmental factors and test errors, the current remains basically unchanged. This is because the galloping frequency of the oscillator remains basically unchanged at high wind speeds.

[0049] Connect the electrical appliances in series between SPC and DEC, use it as a device similar to a current source, and use a rectifier bridge to connect the lithium battery to charge the lithium battery. Figure 7 As shown, the whole device is placed under low wind speed (2.4m / s) for testing, and static electricity can be charged into the lithium battery, which confirms the application prospects of the present invention. The realization of this function will provide more possibilities for the wider application of DEG.

[0050] The present invention drives the U-shaped connecting frame to swing left and right through the galloping vibration of the vibrator, and then the two ends of the vibrating rod continuously hit the dielectric elastomer film under the action of the spring, which is particularly suitable for converting wind energy into electrical energy under low wind speed conditions. The design of the double dielectric elastomer film can generate double electrical energy at the same time. In addition, the positions of the two hinge points in the U-shaped connecting frame can be adjusted according to actual conditions to change the amplitude of the left and right swings, so that the dielectric elastomer film works in the best state.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A wind energy collection device for low wind speeds, characterized in that: It comprises a bracket (1), a spring (2), a dielectric elastomer film (3), a U-shaped connecting frame (4) and a vibrator (5); The bracket plays a supporting and fixing role, and the U-shaped connecting frame is hinged to the bracket so that the U-shaped connecting frame can swing left and right around the straight line where the hinge point is located; a vertically arranged vibrator is installed on one side of the hinge point of the U-shaped connecting frame, and a vertical rod parallel to the vibrator is installed on the other side; a spring and a vibrating rod perpendicular to the plane where the U-shaped connecting frame is located are arranged on the vertical rod, and both ends of the spring are fixed by the bracket, and the middle part of the spring is connected to the vertical rod, and a pair of dielectric elastomer films are arranged on both sides of the vibrating rod, and a distance is left between the end of the vibrating rod and the dielectric elastomer film; The two end surfaces of the dielectric elastomer film are provided with electrodes and connected to the electric energy collection circuit. As the dielectric elastomer film is stretched and compressed, the capacitance changes, thereby changing the internal connection relationship of the electric energy collection circuit to generate and collect electric energy; The electric energy collection circuit includes a second-order self-bias circuit, an electret electrostatic voltage source, a rectifier bridge and a voltage-stabilizing diode; the electrodes on both sides of the dielectric elastomer film, the second-order self-bias circuit, the voltage-stabilizing diode and the rectifier bridge are respectively connected in parallel with the electret electrostatic voltage source; The second-order self-bias circuit includes a diode D1, a diode D2, a diode D3, a diode D4, a diode D5 and an internal capacitor, wherein the internal capacitor includes a first capacitor and a third capacitor with a capacitance value of C, and a second capacitor and a fourth capacitor with a capacitance value of C / 2; The five diodes are connected in series and connected to an electret electrostatic voltage source, and the cathode of the series-connected diode D1 is connected to the anode of the electret electrostatic voltage source, and the anode of the diode D5 is connected to the cathode of the electret electrostatic voltage source; one end of the first capacitor is connected to the anode of the diode D2, and the other end is connected to the anode of the electret electrostatic voltage source; one end of the second capacitor is connected to the cathode of the diode D2, and the other end is connected to the cathode of the electret electrostatic voltage source; one end of the third capacitor is connected to the anode of the diode D4, and the other end is connected to the anode of the electret electrostatic voltage source; one end of the fourth capacitor is connected to the cathode of the diode D4, and the other end is connected to the cathode of the electret electrostatic voltage source; The wind energy collection method of the wind energy collection device comprises: The electrodes on both sides of a pair of dielectric elastomer films are respectively connected to an electric energy collection circuit. In an initial state, an electret electrostatic voltage source injects charges into the second-order self-bias circuit and the dielectric elastomer film, so that both ends of the dielectric elastomer film and both ends of the second-order self-bias circuit have equal initial low voltages. When wind blows through the vibrator, the vibrator vibrates, driving the U-shaped connecting frame to swing left and right. Driven by the U-shaped connecting frame and the action of the spring, the two ends of the vibrating rod continuously hit the dielectric elastomer films on both sides, causing the impacted dielectric elastomer films to continuously produce tensile-compressive deformation, resulting in a change in capacitance; among them, when the dielectric elastomer film is hit by the vibrating rod, the voltage on both sides of the dielectric elastomer film decreases, and the dielectric elastomer film is charged by the second-order self-bias circuit; when the dielectric elastomer film is released, the voltage on both sides of the dielectric elastomer film increases, and the dielectric elastomer film is charged to the second-order self-bias circuit.

2. A wind energy collection device for low wind speed according to claim 1, characterized in that: The end of the vibrating rod is provided with a rubber ring.

3. A wind energy collection device for low wind speed according to claim 1, characterized in that: The dielectric elastomer film is fixed on both sides of the vibration rod through a pair of mounting plates, and the plane where the dielectric elastomer film is located is perpendicular to the motion arcs at both ends of the vibration rod.

4. A wind energy collection device for low wind speed according to claim 1, characterized in that: The low wind speed range is 1 - 4 m / s.

5. A wind energy collection device for low wind speed according to claim 1, characterized in that: The vibrator is a square column or a trapezoidal column.

6. A wind energy collection device for low wind speed according to claim 1, characterized in that: The alternating current on both sides of the dielectric elastomer film is converted into direct current through a rectifier bridge for supplying power to the outside.

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