GB2490377A

GB2490377A - Wind driven rocking elements acting on thrust plate

Info

Publication number: GB2490377A
Application number: GB201121414A
Authority: GB
Inventors: Graham Russell Lee; Trevor Charles Hayes
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-12-13
Filing date: 2011-12-13
Publication date: 2012-10-31
Anticipated expiration: 2031-12-13
Also published as: GB2490377B; GB201021020D0; GB201121414D0

Abstract

A wind driven electrical generating system comprising multiple independently moveable wind capture elements 101 of varying size, a coupling mechanism 106 to convert the movement and bending force of the elements into a combined downward force on a thrust plate or plates and an electricity generating element or elements 104 to convert the downward force of the thrust plate into electric power. The wind capture elements may be flexible at an upper portion 102 to prevent damage in strong winds and rigid in a lower portion 103. Preferably the coupling mechanism comprises a grid with multiple apertures, to hold the wind capture elements and provide a fixed pivot point, and a shaped bearing 105 fixed to the lower end of each wind capture element adapted to transfer pressure downwards to the thrust plate. The electricity generating elements may be piezo-electric crystals or reverse electro wetting on dielectric or micro-electric mechanical systems.

Description

Variable Wind Harvesting, Power Aggregation and Electricity Generation

Field of Invention

This invention relates generally to converting wind power into electrical power, and more especially to harvesting wind power without turbines.

Background of the Invention

Our invention provides a commercially viable means of harvesting variable wind power by mechanically aggregating wind pressure through collectors, then harnessing the combined mechanical effect to stress devices that produce electrical power. The design of the electrical generating system makes it practical to stack a plurality of systems in horizontal layers as well as in vertical arrays, unlike turbines.

Additionally, our invention is designed to be commercially attractive being modular, scalable and standardised using some of the standards developed for domestic photovoltaic (PV) solar panel installations. Electrical outputs from a plurality of modules and systems are connected with industry standard interfaces, allowing wind modules and solar panels to be combined in an array.

Other Approaches The most common method of converting wind energy into electrical energy makes use of turbines; they convert wind energy into the mechanical rotation of a shaft which, directly or indirectly, drives a conventional electrical generator. These devices are becoming widely deployed, but their range of application is limited. They do not perform well, and sometimes not at all, in situations where the wind is gusting, frequently changing direction, or is varying in strength.

The Cornell Computational Synthesis Laboratory investigated harvesting wind power through Flapping Piezo-Leaf Generators' http://ccsl.mae.cornell.edu/node/116 but this proposal has not been carried through to production. It suffers from the limitation, that because each leaf is mechanically connected to a single piezo-electric crystal, the costs of materials and construction and the challenges of maintaining the system in operation, could limit its potential for commercial exploitation.

Sustainable Dance Club' http://www.sustainabledanceclub.com/index. php?t=txt&tx=3 markets an application of piezo-electric crystals which converts the varying pressure created by dancers into electricity to power dance floor lights. While this specialist approach may well be transferable to more general-purpose power generation, it is not easily adaptable for use in wind power applications.

Disclosure of Invention

According to a first aspect of the invention, there is provided a wind-driven electrical generating system comprising: a plurality of wind-capture elements of differing size, each able to independently move in response to movement of air; a coupling mechanism to convert the movement and bending force of said multiple wind-capture elements moving independently or together into a combined downward force on a thrust-plate or set of thrust plates; one or more electricity generating elements to convert the downward force of the said thrust plates into electric power.

The wind-capture elements are adapted to be flexible in an upper portion in order to reduce or eliminate the possibility of damage from strong winds and provide a mechanism for storing a proportion of captured wind energy in the said electricity generating elements as they deform under pressure from the wind.

The wind-capture components are adapted to be rigid in a lower portion in order to efficiently transfer energy to the said coupling mechanism.

The coupling mechanism comprises: a grid with a plurality of apertures adapted to hold the said wind-capture elements in position and provide a fixed pivot point for the elements; and a shaped bearing fixed to the lower end of each wind-capture element adapted to transfer pressure downwards to the said thrust-plate when the wind-capture elements are subject to wind force in any horizontal direction.

The electricity generating elements are adapted to create electrical power individually or in concert, under compressive and de compressive force exerted by the said thrust-plate.

The electrical generating elements are adapted to create electrical power individually or together, under varying wind conditions from intermittent gusts to strong steady winds.

The electrical generating elements are adapted to respond to steady wind pressure in harmonic motion within a range of frequencies capable of being transformed into electrical power by said electrical generating elements.

The electricity generating elements include piezo-electric crystals, reverse electro wetting on dielectric, or micro-electro-mechanical systems.

A racking apparatus allows multiple wind-generating systems to be stacked in vertical arrays and in horizontal layers.

A system of electrical connectors and adapters allows the electrical outputs from multiple wind-generating systems to be combined.

Key Components Our invention is a unique application of known technology. The key components of our invention are Generation Devices fabricated from commercially available components, wind collectors such as a fin tipped reed sheaf, and mechanical motion/vibration converters.

Mechanical Aggregation and Thrust Transfer Typically, our invention uses a thrust plate or thrust plates which transfer power from the wind collector to the Generation Device. As the wind gusts the wind collector (e.g. a fin tipped reed sheaf) moves in sympathy with the wind, transferring motion to the thrust plate. The wind collectors are different sizes and can move in any lateral direction and rotate axially through 3600. This enables the wind collectors to resonate at different frequencies and creates a variety of wind paths through the collecting array enhancing the chaotic wind motion. In a chaotic wind, the elasticity built into the system will provide repeated rebound, resulting in an oscillation of the entire thrust plate at a frequency between 1 Hz and 25 kHz, depending on the dimensions of the components of the system. Vibration within this frequency range will cause the Generation Device to generate electrical power. The thrust plate acts directly on the Generation Devices, compressing them, and thereby generating power. The output is rectified to provide a consistently polarised DC voltage. When this is connected to other modules in an array similar to solar panels, it provides useful amounts of DC power. We expect the electrical output to be standardised to connect seamlessly to industry standard invertors (DC to AC power converters) as used in domestic solar arrays.

Examples of Electrical Generation Devices A variety of devices can be used to generate electrical power from mechanical energy. The selection of Generation Devices for this invention is dependent on the specific implementation, the efficiency of conversion and the commercial cost of the components. Examples of Generation Devices are: Piezo-electric crystals. Piezo-electric crystals produce an electric charge when mechanically stressed. These are already widely used in a variety of applications such as motion detectors, vibration detectors, electric guitar pickups, contact microphones, gas lighters and other applications for converting mechanical energy to electrical energy in relatively small quantities. Recent developments in piezo-electric crystal design and fabrication have increased the efficiency of conversion of mechanical energy to electrical energy * Reverse Electro Wetting on Dielectric (REWOD). REWOD is a mechanical-to-electrical energy conversion method based on the reverse electrowetting phenomenon. Electrical energy generation is achieved through the interaction of arrays of moving microscopic liquid droplets with novel nanometer-thick multilayer dielectric films. Advantages of this process include the production of high power densities, up to 103W m-2; the ability to directly utilise a very broad range of mechanical forces and displacements; and the ability to directly output a broad range of currents and voltages, from several volts to tens of volts. These advantages make this method uniquely suited for high-power energy harvesting from a wide variety of environmental mechanical energy sources.

* Micro-Electro-Mechanical Systems (MEMS). MEMS, is a technology that in its most general form can be defined as miniaturised mechanical and electro-mechanical elements (i.e., devices and structures) that are made using the techniques of microfabrication. The critical physical dimensions of MEMS devices can vary from below one micron at the lower end of the dimensional spectrum, all the way to several millimetres. Likewise, the types of MEMS devices can vary from relatively simple structures having no moving elements, to extremely complex electromechanical systems with multiple moving elements under the control of integrated microelectronics. While the functional elements of MEMS are miniaturised structures, sensors, actuators, and microelectronics, the most notable (and perhaps most interesting) elements are the microsensors and microactuators. Microsensors and microactuators are appropriately categorised as "transducers", which are defined as devices that convert energy from one form to another. In the case of microsensors, the device typically converts a measured mechanical signal into an electrical signal.

Other Generation Devices can be used which, with a potential continuing reduction in cost, can form part of a system designed to harvest wind power and meet the requirements of commercial and residential power consumers.

Brief Description of Drawings

Figure 1 is a schematic representation of the invention and shows the Principle of Operation (Not to Scale and exaggerated for illustration).

Figure 2 is a plan view of a system module (Not to Scale). Typically the dimensions of the system module will conform to industry standards for solar panels. As such the dimensions are expected to range from H: 525mm x W: 350mm through H: 1500mm x W:680mm. Typically the depth of a panel is 35mm.

Figure 3 is a sectional front elevation of a system module reveals the mechanics of the system (Not to Scale).

Figure 4 is a side elevation of a system module (Not to Scale).

Best Mode for Carrying Out the Invention

For a more complete explanation of the present invention and the technical advantages thereof, reference is now made to the following description and the accompanying drawings in which: Figure 1 is a schematic representation of the invention and shows the Principle of Operation (Not to Scale and exaggerated for illustration).

The drawing illustrates the rigid frame [110] of a system module, with a thrust plate' [106] sitting above Generation Devices [104]. The fins [101] move under the pressure of wind and transfer motion to the flexible reed stem [102], which in turn transfers motion to the rigid reed stem [103]. The rigid reeds [103] thread through holes in the frame [110] enabling the reed stems [103] to move laterally, vertically and axially. The motion of the reeds [103] is transferred through the movement of the omni-cams [1051 increasing the pressure on the thrust plate [106]. The omni-cam [105] is symmetrical around the axis of the reed [103] and can rotate through 360°. The thrust plate [1061 aggregates the movement of one or more omni-cams [105] and is free to move vertically in both directions. The thrust plate [106] transfers the aggregate pressure to the Generation Devices [104] below it. The number of Generation Devices [104] and the number of trust plates [106] in the system module can be varied, and will determine the efficiency of the wind collector in the anticipated wind conditions it is designed to harness. The major components are expected to be off the shelf or fabricated from currently commercially available materials to minimise costs. The system module is typically within the same size range as a solar panel.

Figures 2, 3, & 4 show the plan, front elevation and side elevation views of a system module. The views are sectioned to reveal the mechanics of the system.

Important Features of the Invention * The frame and housing [110] is fabricated from a rigid material such as aluminium or composite material.

* The frames [110] are modular and may be dimensioned and designed to slot into a standard size solar panel frame.

The wind is captured by dart fins or bulrush-shaped heads [101].

* The reeds are rigid at the base and flexible toward the tip to reduce the risk of damage from strong winds [102] and [103].

* The reeds are mounted in a lattice arrangement (See Figure 3) * The reeds can move vertically and axially around 360° through the flexible bearing [107].

* The thrust plate(s) [106] are driven by rigid omni-cams [105] at the root of reed stem [103].

* Generation Devices [104] are stimulated by the thrust plate(s) [106] to provide the electrical power.

* The thrust plate(s) [106] rest on flexible supports [108] which restore the thrust plate(s) [106] to the quiescent position.

* Each Generation Device [104] has a by-pass/rectifying diode and voltage regulating network.

* The electrical output from Generation Devices [104] may be combined in a variety of series/parallel combinations to deliver power at various combinations of voltage and current to match the requirements of connected combination/rectification equipment.

* The output from multiple Generation Devices [104] is combined into standard modular connectors as used in solar panels.

* Each module has vents [109] to allow water and detritus to be released.

* The modules can be installed in horizontal configurations with the option for multiple layers.

* The modules can be installed at an angle on pitched roofs, with a possible decrease in generating output depending on the direction of prevailing winds.

* The modules can be used alongside solar panels, with, for example solar panels on rooftop areas exposed to sunlight, with wind-generating modules positioned in shaded areas.

* The modules are suitable for flat house roofs, warehouses, industrial premises, roof of multi-story car-parks, apartment blocks, farms, open spaces, along roadsides and railway tracks and many other locations, including those in which traditional rotor-driven turbine generation would not be practical or acceptable.

Claims

Claims 1. Awind-driven electrical generating system comprising: a plurality of wind-capture elements of differing size, each able to independently move in response to movement of air; a coupling mechanism to convert the movement and bending force of said multiple wind-capture elements moving independently or together into a combined downward force on a thrust-plate or set of thrust plates; one or more electricity generating elements to convert the downward force of the said thrust plates into electric power.
2. The electrical generating system of Claim 1 wherein said wind-capture elements are adapted to be flexible in an upper portion in order to reduce or eliminate the possibility of damage from strong winds and provide a mechanism for storing a proportion of captured wind energy in the said electricity generating elements as they deform under pressure from the wind.
3. The electrical generating system of Claim 1 wherein said wind-capture components are adapted to be rigid in a lower portion in order to efficiently transfer energy to the said coupling mechanism.
4. The electrical generating system of Claim 1 wherein said coupling mechanism comprises: a grid with a plurality of apertures adapted to hold the said wind-capture elements in position and provide a fixed pivot point for the elements; and a shaped bearing fixed to the lower end of each wind-capture element adapted to transfer pressure downwards to the said thrust-plate when the wind-capture elements are subject to wind force in any horizontal direction.
5. The electrical generating system of Claim 1 wherein said electricity generating elements are adapted to create electrical power individually or in concert, under compressive and de-compressive force exerted by the said thrust-plate.
6. The electrical generating system of Claim 1 wherein said electrical generating elements are adapted to create electrical power individually or together, under varying wind conditions from intermittent gusts to strong steady winds.
7. The electrical generating system of Claim 1 wherein said electrical generating elements are adapted to respond to steady wind pressure in harmonic motion within a range of frequencies capable of being transformed into electrical power by said electrical generating elements.
8. The electrical generating system of Claim 1 wherein one or more electricity generating elements include piezo-electric crystals, reverse electro wetting on dielectric, or micro-electro-mechanical systems.
9. The electrical generating system of Claim 1 wherein a racking apparatus allows multiple wind-generating systems to be stacked in vertical arrays and in horizontal layers.
10. The electrical generating system of Claim 1 wherein a system of electrical connectors and adapters allows the electrical outputs from multiple wind-generating systems to be combined.