Patent Application
20160201646
This invention relates to generating electrical power from airflow.
The ever-increasing demand for sustainable, environmentally-friendly power generation from wind is currently met with devices such as the wind turbine. Although wind turbines are the most commonly used method of generating electrical power from wind, they have several inherent drawbacks. These devices are costly, difficult to construct, install, and maintain, highly visible, noisy, large, susceptible to damage, and relatively difficult to transport and assemble. Their tall stature makes them susceptible to damage from flying debris, birds, and even low flying planes. The U.S. Military has also voiced concerns claiming the placement of wind turbines in a radar system's line of sight may adversely impact the unit's ability to detect threats. Rotating wind turbines are also not suitable for military applications that require quiet, inconspicuous power generation in remote locations. Additionally, when facing high wind speeds, a mechanical brake must be applied, creating losses and inefficiencies. Therefore, there is a need for portable, non-rotating devices that can generate useful amounts of electrical power in a quiet, inconspicuous manner and for improvements thereto.
A system created by Vortex Hydro Energy uses the principle of vortex-induced vibration in water to harness wave energy. The company has developed a device called the Vortex Induced Vibration Aquatic Clean Energy (VIVACE). This product uses vortex-induced vibration as a primary means of creating mechanical motion from fluid flow. The system is designed to operate underwater in ocean currents. This system uses an electrically variable spring constant system that dynamically changes the natural frequency to allow for optimization at different flow speeds. This system is unsatisfactory for wind power generation due to the large difference between the fluid flow properties of air. The frequency of vortex shedding in air is much faster that the shedding frequency in water. Therefore, matching the system's natural frequency with the shedding frequency would result in an extremely large spring constant. A spring this size would require a great deal of force to move. The lift characteristics of this application do not provide enough lift to overcome this spring constant, and no vibrations will occur.
Additionally, wind speeds can vary, so there is a need for a system that can function at a variety of wind speeds, as well as while wind speeds are varying.
Therefore, a need exists for portable, non-rotating devices that can generate useful amounts of electrical power from wind in a quiet, inconspicuous manner and for improvements thereto, such as a control system for such devices.
Aspects of the invention relate to a control system for a non-rotating wind energy generator. In one or more embodiments, the control system comprises a sensor that senses at least one of: an amplitude of oscillation of a bluff body of the non-rotating wind energy generator, a power output of a linear alternator system of the non-rotating wind energy generator, a voltage output of the linear alternator system of the non-rotating wind energy generator, and a current output of the linear alternator system of the non-rotating wind energy generator. In one or more embodiments, the control system comprises a damper that applies a damping force to the bluff body based in part on at least one of the amplitude, the voltage output, the current output, and the power output.
In one or more of the preceding embodiments, the damper increases the damping force based at least in part on a first sensor input. In one or more of the preceding embodiments, the damper decreases the damping force based at least in part on a second sensor input. In one or more of the preceding embodiments, the damper increases the damping force when the amplitude is above a first threshold and the damper decreases the damping force when the amplitude is below a second threshold. In one or more of the preceding embodiments, the damper applies a maximum damping force when the amplitude is above a maximum threshold until the amplitude is below a minimum threshold. In one or more of the preceding embodiments, the damper waits a predetermined time before changing the damping force. In one or more of the preceding embodiments, applying the damping force comprises applying a load to the linear alternator system. In one or more of the preceding embodiments, the system comprises a controller that receives an input from the sensor and sends a control instruction to the damper, wherein the damping force is based in part on the control instruction. In one or more of the preceding embodiments, the system comprises a battery charge controller that controls charging of a battery, wherein the sensor determines a charge level of the battery. In one or more of the preceding embodiments, the damper comprises at least one of a variable resistor and a transistor that applies a variable resistance to the linear alternator system of the non-rotating wind energy generator to control the damping force. In one or more of the preceding embodiments, the damper comprises a transistor and a variable resistor that each apply a variable resistance to the linear alternator system of the non-rotating wind energy generator to control the damping force. In one or more of the preceding embodiments, the damper controls the damping force based in part on a pulse-width modulation signal. In one or more of the preceding embodiments, the sensor comprises at least one optical sensor. In one or more of the preceding embodiments, the sensor comprises: a first at least one sensor that determines whether the amplitude is above a first threshold; and a second at least one sensor that determines whether the amplitude is above a second threshold.
Aspects of the invention relate to a method of controlling a non-rotating wind energy generator, the method comprising. In one or more embodiments, the method comprises determining at least one of: an amplitude of oscillation of a bluff body of the non-rotating wind energy generator, a power output of a linear alternator system of the non-rotating wind energy generator, a voltage output of the linear alternator system of the non-rotating wind energy generator, and a current output of the linear alternator system of the non-rotating wind energy generator; and applying a damping force to the bluff body based in part on at least one of the amplitude, the voltage output, the current output, and the power output.
In one or more of the preceding embodiments, the method comprises increasing the damping force based at least in part on a first sensor measurement. In one or more of the preceding embodiments, the method comprises decreasing the damping force based at least in part on a second sensor measurement. In one or more of the preceding embodiments, the method comprises at least one of: increasing a damping force when an amplitude of oscillation of a bluff body of the non-rotating wind energy generator is above a first threshold; and decreasing a damping force when the amplitude is below a second threshold. In one or more of the preceding embodiments, the method comprises waiting a predetermined time before changing the damping force. In one or more of the preceding embodiments, the method comprises charging a battery using the non-rotating wind energy generator; controlling a charging rate of the battery; and determining a charge level of the battery. In one or more of the preceding embodiments, the method comprises controlling the damping force based in part on varying a resistance of a variable resistor. In one or more of the preceding embodiments, the method comprises controlling the damping force based in part on a pulse-width modulation signal.
Aspects of the invention relate to a non-rotating wind energy generating apparatus, comprising: a flat spring bluff body assembly operable to initiate and sustain oscillatory motion in response to wind energy, wherein the flat spring bluff body assembly comprises one or more pairs of parallel flat springs; and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body.
In one or more of the preceding embodiments, the flat spring bluff body assembly comprises: a frame movably supporting at least one beam; the one or more flat springs attach the beam to the frame; the linear alternator system comprises: at least one electromagnetic coil attached to one of the beam or the frame; at least one magnet attached to one of the frame or the beam; and the beam when exposed to wind causes the at least one electromagnetic coil to pass the at least one magnet. In one or more of the preceding embodiments, the apparatus comprises one or more additional beams; one or more additional flat springs; wherein the one or more additional flat springs attach the one or more additional beams to the frame.
Aspects of the invention relate to a non-rotating wind energy generating apparatus, comprising: a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy, wherein the suspended bluff body has at least one of the following cross-sectional profiles: an ellipse with a depth to height ratio between 8/16 and 14/16; a rectangle with a depth to height ratio greater than 0 and less than 1; a multiple D-shape with a first beam oriented in an opposing direction to a second beam, wherein the depth to height ratio of each beam is between 1/4 and 3/4; a multiple D-shape with a first beam oriented in a same direction as a second beam, wherein the depth to height ratio of each beam is between 1/4 and 3/4; a biconvex shape with a depth to height ratio between 8/16 and 14/16; a diamond shape with a depth to height ratio between 4/10 and 7/10; and a rounded rectangle with a depth to height ratio greater than 1/2 and less than 1; and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body.
In one or more of the preceding embodiments, the suspended bluff body comprises a frame movably supporting at least one beam; one or more first springs; one or more second springs; wherein the one or more first springs attach a first portion of the frame to a first portion of the beam and the one or more second springs attach a second portion of the frame to a second portion of the beam such that the beam is suspended between the first and second portions of the frame; and linear alternator system comprises: at least one electromagnetic coil attached to one of the beam or a third portion of the frame; at least one magnet attached to one of the third portion of the frame or the beam; wherein motion of the beam when exposed to wind causes the first electromagnetic coil to pass at least one magnet. In one or more of the preceding embodiments, the first, second, and/or third portions of the frame can be the same portions of the frame. In one or more of the preceding embodiments, the apparatus comprises a voltage multiplier circuit that generates a DC voltage from an AC voltage output by the linear alternator system, wherein the DC voltage is higher than the AC voltage.
These and other aspects and embodiments of the disclosure are illustrated and described below.
The foregoing and other objects, features and advantages of the invention will be apparent from the following description of embodiments of the invention, as illustrated in the accompanying drawings.
Aspects of this invention relate to improvements to a non-rotating wind energy generator. In one aspect, a device is provided to generate electricity from non-rotational motion caused by wind flow. Wind is typically characterized as unsteady flow; therefore the device is capable of operation in unsteady flow characteristics. Aspects and embodiments of non-rotating wind energy generators are described in further detail in related application Ser. No. 14/054,820, filed Oct. 15, 2013 entitled “Non-Rotating Wind Energy Generator,” the content of which is hereby incorporated by reference herein in its entirety.
Non-rotating wind energy generation is provided by first establishing non-rotating motion from wind flow, and then using that motion to generate electricity. In one aspect, a device does not use rotational motion similar to wind turbines currently on the market, but instead, the device uses self-excited oscillation caused, for example, by the fluid flow principle of vortex shedding, transverse galloping, or some combination thereof, to generate oscillatory, linear motion of a beam.
In one or more embodiments, the beam design is selected to provide self-excited vibrations when exposed to wind. Self-excited vibration is a phenomenon in which the motion of a system causes it to oscillate at its natural frequency with continually growing amplitude. In one or more embodiments of the invention, vortex shedding will initiate self-excited vibration of a beam. In one or more embodiments, a beam will continue to oscillate at the system's natural frequency when exposed to a wind flow. In one or more embodiments, the system controls the amplitude of oscillation using springs. In further more embodiments, the system utilizes stops to limit the amplitude of oscillation.
In one aspect, a beam is slidably mounted in a frame to provide oscillatory motion of the beam due to vortex shedding, transverse galloping, or a combination thereof, that is substantially perpendicular to the wind direction, or which has a component that is substantially perpendicular. The beam can be equipped with at least a pair of springs positioned above and below the beam to provide restorative force to the beam subjected to vortex shedding, transverse galloping, or a combination thereof. This provides oscillatory motion of the beam while in wind contact. The springs can be secured to the frame using conventional methods such as latches, hooks, welds, bonds and the like. Due to the high stress experienced by the spring or other joining device, the securing method desirably provides high material strength and low fatigue over its life under cyclic loading. To maintain a constant spring rate, coil diameter and/or number of coils can be increased as wire diameter increases. Linear alternators can be located near both ends of the beam; however, they can also be located anywhere in any number. They generate electrical power when the beam is in motion. A damping system can be provided to further control the amplitude of the oscillations.
A non-rotating wind energy generating device can use the interaction of the beam with wind to induce vortex shedding, transverse galloping, and linear motion, which is then converted to electrical power with electromagnetic inductors, also referred to as linear alternators. In one or more embodiments, the linear alternators incorporate magnets that are concentric with the wire coil. Other embodiments may use multiple pairs of parallel, stationary magnets and electromagnetic coils, such as electromagnetic coils with a circular or square shape, that are fixed to a beam that passes between the magnets during operation. The use of a parallel magnet/coil configuration has been experimentally proven to be superior to a concentric magnet/coil configuration in at least one embodiment. This configuration permits a larger clearance between the magnets and coils. This helps prevent damping caused by rubbing during beam motion. The use of parallel stationary magnets increases the strength of the magnetic field in the linear inductors, also referred to as linear alternators. Magnetic field strength is a contributing factor of electrical power generation in magnetic inductors using electromagnetic induction. Other embodiments may involve individual magnets and coils configured such that one pole surface of the magnet passes in close proximity to the flat surface of the coil during motion of either component respective to the other. The configuration of the components results in the coil being exposed to a changing magnetic field during oscillatory motion of the beam.
Some of the potential applications for a non-rotating wind energy generating device include: powering electronic devices using energy harvested from airflow in HVAC ducts; supplying primary or supplemental power to wireless sensors; generation of usable electrical energy from naturally occurring airflow (e.g. window draft) in and out of residential or commercial buildings due to wind or changes/differences in temperature or pressure; directly powering LED lighting, radios, other electronic devices; ability to recharge batteries used in electronic devices; directly powering LCD or LED based signage.
In an embodiment, wind energy is used to induce self-excited oscillations of the suspended beam 103. The fluid flow phenomena of vortex shedding, transverse galloping, or a combination thereof, are harnessed to initiate and sustain oscillatory motion of one or more beams 103. This reciprocating motion is used to generate electricity via electromagnetic induction using the linear alternator assemblies 102 comprising coils and magnets 101. In some embodiments, magnets are stationary and electromagnetic coils, such as wire coils, move relative to the magnets. In further embodiments, electromagnetic coils, such as wire coils, are stationary and magnets move relative to the electromagnetic coils. In still further embodiments, both magnets and electromagnetic coils, such as wire coils, may move.
When vortex shedding and transverse galloping occur in the system, such as when the vortex shedding frequency matches the natural frequency of the system, extremely large amplitude of motion will be achieved. In some embodiments, the spring system controls and maintains oscillatory behavior. The springs may have the same spring tension in order to keep the beam suspended. In some embodiments, the number, size, and stiffness of the springs may be varied. Oscillatory movement may not be solely caused by vortex shedding. A phenomenon called transverse galloping, which can result in self-excited oscillations, may also be responsible for continuous motion. In some embodiments, after vortex shedding induces a small displacement input, the motion of the system itself due to transverse galloping causes it to oscillate at its natural frequency while in a wind flow. In some embodiments, springs 404 range in constants from 0.01 lbs/in up to 3 lbs/in, and more particularly from 0.1 lbs/in up to 3 lbs/in.
In some embodiments, a second beam (or more) may be mounted in parallel to the first beam for a two degree (or more) of freedom system.
In an embodiment, the beam is hollow on the inside and has a D-shape, and inductor assemblies are attached to each end of the beam. In an embodiment, the D-shaped beam has a length of 24 inches (exclusive of the inductor assemblies), a diameter of 2 inches, wall thickness of ⅛ inch, and a weight of 0.5 pounds. In an embodiment, an equivalent spring stiffness of 0.5 lbs/in may be used with a 0.5 lb beam.
In other embodiments, other beam shapes may be used. For example, the beam may be a square, a rectangle, a cylinder, a reversed D-Beam (where the wind is primarily incident on the flat portion of the beam rather than the round portion), and an equilateral wedge in either a “greater than” or “less than” orientation relative to the incident wind. Additionally, in some embodiments, the surface of the beam may be smooth, and in further embodiments, the surface may be rough, uniformly or at selected locations. In some embodiments, the beam may be fitted with weights for optimal mass to adjust the frequency and amplitude.
One or more beams can be used in a non-rotating wind energy device. In some embodiments, the plurality of beams can include a rigid spacer between beams and the multi-beam system can be secured to the frame by springs attached to the upper and lower beams. In other embodiments, the plurality of beams can be joined by springs to one another and to the frame.
Linear electromagnetic induction is provided for generating usable amounts of electrical power. Faraday's Law states that voltage is equal to the rate of change of magnetic flux. Faraday's Law and magnetic flux are shown in the equations below. A permanent magnet forms the magnetic field and the energy is captured via a loop of wire moving through that field.
ε is the induced voltage, φB is the magnetic flux, B is the magnetic field strength, A is the cross sectional area of the loop, and θ is the angle that the magnetic field makes with a vector normal to the area of the loop.
In one or more embodiments of a non-rotating wind energy generator, wind can cause beam oscillations to grow to and potentially exceed a maximum amplitude allowed by the springs. In other cases, wind may result in smaller oscillations than desired, which can lead to inefficient energy generation. Further, in many cases, wind speeds may vary, potentially causing both large and small oscillations. To address these and other problems, one or more embodiments comprise a control system to modulate the amplitude of oscillation for a non-rotating wind energy generator.
In one or more embodiments of the invention, sensor 202 senses at least one of an amplitude of oscillation of a bluff body of the non-rotating wind energy generator, a power output of a linear alternator system of the non-rotating wind energy generator, a voltage output of the linear alternator system of the non-rotating wind energy generator, and a current output of the linear alternator system of the non-rotating wind energy generator. In one or more embodiments of the invention, damper 203 applies a damping force to the bluff body based in part on at least one of the amplitude, the voltage, the current, and the power determined by the sensor.
Returning to
In one or more embodiments of the invention, damper 203 can increase the damping force when the amplitude is between a first threshold and a second threshold and can decreases the damping force when the amplitude is between a third threshold and a fourth threshold. Additionally, in one or more embodiments of the invention, damper 203 can apply a maximum damping force when the amplitude is above a fourth threshold. Additionally, the damper can continue to apply the maximum damping until the amplitude is below the first threshold. In one or more embodiments, more or fewer thresholds can be used to control the damping. For example, the damper 203 could use a different number of thresholds and could increase the damping force between certain thresholds and could decrease the damping force between others. In one or more embodiments of the invention, the damper 203 can apply a damping force by applying a load to the linear alternator system of a non-rotating wind energy generator. In one or more embodiments, increasing the load can increase the damping force by drawing current more rapidly from the non-rotating wind energy generator and decreasing the load can reduce the damping force by drawing current more slowly from the non-rotating wind energy generator. In one or more embodiments of the invention, the concepts of eddy currents, Lenz's Law, or a combination of both can be utilized to apply a damping force on the beam. Magnetic flux from magnets located on the beam can create eddy currents in electrically conductive materials (e.g. copper and aluminum). These eddy currents can cause a damping force on the beam, which can cause the beam to slow and reach desired maximum amplitude.
In one or more embodiments of the invention, the damper 203 can comprise at least one of at least one variable resistor and at least one transistor that applies a variable resistance to the linear alternator system of the non-rotating wind energy generator to control the damping force. The resistors and transistors can be arranged serially, in parallel, or in a combination of both to provide a variety of loads to a current path from the non-rotating wind energy generator via input 201. In one or more embodiments, a transistor can be used to provide a fine adjustment to the load and variable resistors can be used to provide course adjustment to the load. In an exemplary embodiment, a transistor providing fine load adjustment can be placed in series with a variable resistor providing course load adjustment. The variable resistor can comprise fixed resistors placed in parallel that can be selectively included in the current path to vary the resistance of the variable resistor. In other embodiments, other combinations are possible. For example, transistors can also be used for course adjustment and variable resistors can also be used for fine adjustment. Damper 203 in
In one or more embodiments of the invention, the damper 203 can vary the load based on a pulse width modulated (PWM) signal. For example, the damper 203 can apply a load when the PWM signal is high and apply a minimal load or on load when the PWM signal is low, or vice versa. Additionally, in one or more embodiments, the damper can apply one load when the PWM signal is high and another load when the PWM signal is low. The PWM signal can be based on one or more of an input from the sensor 202, a voltage, current, or power input from input 201, a battery level, and other parameters of the system. In still further embodiments of the invention, the load can be varied with other signals besides PWM signals. For example, variable resistance values could be signaled by an amplitude modulated signal, a phase modulated signal, a frequency modulated signal, and through other types of signals and communication methods.
In one or more embodiments of the invention, damper 203 can wait a predetermined time, e.g., a delay is implemented, before changing the damping force. In one or more embodiments, the damper 203 can also wait a variable amount of time before changing the damping force. Additionally, a waiting time can be used to delay the sensor such that the sensor 202 waits to take additional measurements during the delay. The delay can be specified in any units. For example, it can be specified in seconds or oscillations. In one or more embodiments, a delay can be used, for example, to prevent the system from reacting too quickly to a change in oscillations. By delaying adjustments to the damping, the control system can allow the oscillating beam to reach a new oscillating amplitude before making further adjustments to the damping force. In one or more embodiments, the delay can be in the range of 1-10 oscillation cycles. In one or more embodiments, other delays or no delay can be utilized.
In one or more embodiments of the invention, the control system 200 can include a battery, supercapacitor, and/or other storage device (not shown). The control system 200 can charge the battery, supercapacitor, and/or other storage device using power, voltage, and/or current from a non-rotating wind energy generator. The control system 200 can additionally include a battery, supercapacitor, and/or other storage device charge controller that controls a charging of the battery, supercapacitor, and/or other storage device. Further, in one or more embodiments, sensor 202 can include one or more battery, supercapacitor, and/or other storage device charge level sensors that determine a charge level of the battery. In one or more embodiments, control system 200 can include one or more separate battery charge, supercapacitor, and/or other storage level sensors. In one or more embodiments, a control system can use an input from a battery charge monitor to control or halt beam oscillations to prevent overcharging a battery, supercapacitor, or other storage device. This can protect the storage device from damage associated from overcharging. Halting beam oscillations when the storage device is fully charged or no electricity generation is desired can prevent wear on the mechanical components of the non-rotating wind energy generator.
In one or more embodiments of the invention, the control system 200 can include an AC to DC voltage rectifier and filter (not shown) to convert an AC signal from a non-rotating wind energy generator to a DC signal. Additionally, in one or more embodiments of the invention, the control system 200 can include a sensor to determine a resistance applied by the damper 203, which can be part of sensor 202 or can be a separate sensor (not shown).
In one or more embodiments of the invention, the controller 204 can receive a sensor signal from sensor 202 representing a sensor value such as the amplitude, position, and/or speed of a non-rotating wind energy generator beam. The controller 204 can also receive a voltage, current, and/or power signal from sensor 202 measured for a voltage, current, and/or power from input 201 representing a voltage, current, and/or power value for a non-rotating wind energy generator. The controller 204 can further receive a signal from the damper 203 and/or from another sensor representing the load applied by the damper 203. In one or more embodiments of the invention, the controller 204 can receive other inputs such as a charge measurement for one or more batteries. Additionally, in one or more embodiments, the controller 204 can receive additional sensor inputs from one or more sensors such as voltage sensor 206.
In one or more embodiments of the invention, the controller 204 can output a control signal to control the damper 203, in response to the various input data. The control signal can be a PWM signal, as well as signals such as amplitude, frequency, or phase modulated signals. In one or more embodiments, the control system 200 can include a PWM to voltage converter (not shown). The PWM to voltage converter can convert a PWM signal from the controller 204 to a voltage signal. The voltage signal can be send from the PWM to voltage converter to the damper 203. In one or more embodiments, the control system 200 can include a voltage to load converter. The voltage to load converter can convert a voltage from the PWM to voltage to a load. In one or more embodiments, the voltage to load converter can be part of damper 203 or can be separate (not shown) from damper 203.
In
In
Additionally, in one or more embodiments, a non-rotating wind energy generator can include one or more flat springs 601, one or more beams 602, one or more flat spring mounting surfaces 603, one or more electromagnetic coils 604, one or more magnets 605, and one or more frames 606, as shown in
Furthermore,
In one or more embodiments of the invention, the flat springs constrain the motion of the bluff body to an arc path determined in part by the geometry and material properties of each flat spring. These properties include the length, thickness, width, modulus of elasticity, and tensile strength, among others.
In one or more embodiments of the invention, the flat springs can be attached to the bluff body such that, as the bluff body oscillates, the leading surface exposed to wind flow remains mostly perpendicular to a plane parallel to the flat springs when they are in a flat, unflexed position. In one or more embodiments of the invention, the flat springs and bluff body can operate effectively when the longitudinal axis of the beam is parallel, perpendicular, or on an angle relative to the earth's surface with the leading surface of the bluff body largely perpendicular to wind flow.
In one or more embodiments of the invention, the flat springs deform in an ‘S’-shape as they flex during oscillatory bluff body motion. In one or more embodiments of the invention, the oscillatory motion of a bluff body attached to one or more flat springs can sweep an arc around an axis parallel to the longitudinal axis of the beam.
In one or more embodiments of the invention, kinetic energy of oscillating flat springs and a bluff body can be converted to usable electrical energy via methods such as a use of a piezoelectric element, an electromagnetic inductor, and/or an electrostatic element.
In
In one or more embodiments of the invention, one or more beam shapes can be used. The beams can be hollow/thin-walled, solid/foam, or partially filled (matrix/lattice). The beams can have a symmetrical design which can permit response to flow incident on either side of the beam and/or can have non-symmetrical designs. The following provides non-limiting examples of possible beam shapes in one or more embodiments of the invention.
In one or more embodiments of the invention, a beam can have an ellipse shaped cross-sectional profile. Effective depth (e) to height (d) ratios include (but are not limited to): e/d=0.6875 (11/16). Effective profile dimensions include (but are not limited to): e=1.203″, d=1.75″.
In one or more embodiments of the invention, a beam can have a rectangular cross-sectional profile. Effective depth (e) to height (d) ratios include (but are not limited to): e/d=0.25. Effective profile dimensions include (but are not limited to): e=0.4075″, d=1.75″.
In one or more embodiments of the invention, a beam can have a Multiple D-Shape or multi-Semicircular cross-sectional profile. The multiple D-shape beam can comprise two or more rigidly connected semicircular sections. The beams can be oriented in opposing directions, which can provide the benefit of symmetry or in the same direction which can provide greater lift force from flow approaching the flat side of the beam. Effective depth (e) to height (d) ratios of each semicircular section include (but are not limited to): e/d=0.5. Effective profile dimensions of each semicircular section include (but are not limited to): e=0.625″, d=1.25″.
In one or more embodiments of the invention, a beam can have a biconvex cross-sectional profile. Effective depth (e) to height (d) ratios include (but are not limited to): e/d=0.6875 (11/16). Effective profile dimensions include (but are not limited to): e=1.203″, d=1.75″.
In one or more embodiments of the invention, a beam can have a diamond shaped cross-sectional profile. Effective depth (e) to height (d) ratio include (but are not limited to): e/d=0.577. Effective profile dimensions include (but are not limited to): e=1.5″, d=2.6″.
In one or more embodiments of the invention, a beam can have a rounded rectangle shaped cross-sectional profile. Effective depth (e) to height (d) ratio include (but are not limited to): e/d=0.75. Effective profile dimensions include (but are not limited to): e=1.5″, d=2.0″, with a 0.5″ flat portion.
In one or more embodiments of the invention, a beam can have a beam with multiple cross sections. A beam with multiple segments with various cross sectional profiles can allow the system to benefit from the differing oscillatory responses of each. For example, different beam profiles can perform better under different wind conditions (e.g. low wind speed range vs. high wind speed range, laminar vs. turbulent flow). A beam with multiple profile segments can offer an overall improved oscillatory response to variable flow conditions.
In one or more embodiments of the invention, the surfaces of the beam exposed to the environment are of a material or coating known to repel the adherence of precipitation (e.g. rain, snow, ice) and other forms of debris (e.g. dirt, animal droppings). A low friction and/or hydrophobic material (e.g. Teflon, HIREC) helps prevent the buildup of material on the beam which could interfere with the fluid flow phenomena involved with beam oscillations.
In one or more embodiments of the invention, the beam's design and material of construction results in the beam appearing partially or completely transparent. The purpose of this transparency is to allow the system to blend in with its surroundings and make the beam more inconspicuous. It also permits lighting from within the beam to be visible on the outside. Materials conducive to this transparent appearance include acrylic.
In one or more embodiments of the invention, the beam is fully or partially transparent and is internally illuminated by LED's located within the beam. The LED's can receive electrical power for operation via the extension springs used to support the beam. The metal springs can act as electrical leads and permit the flow of electricity from the stationary frame to the movable beam.
In one or more embodiments of the invention, LED's affixed to any surface on the stationary frame can shine their light upon the beam.
In one or more embodiments of the invention, the LED's affixed to any part of the generator may shine in any direction and upon any other surface to provide illumination. This may serve the function of a lantern, signal, signage, or some other purpose.
In one or more embodiments of the invention, the generator's frame design and material of construction results in the frame appearing largely transparent. This transparency allows the system to blend in with its surroundings and makes the system more inconspicuous. Materials conducive to this transparent appearance include acrylic.
In one or more embodiments of the invention, the generator's frame can have a horizontal member, which may be optionally located above or below the movable beam. The springs may be attached to a cantilevered horizontal section. Using one horizontal member (as opposed to two) can permit improved, unimpeded fluid flow towards the beam. It can also reduce manufacturing costs.
In one or more embodiments of the invention, a screen can be mounted to the frame that permits fluid flow through the holes in the screen towards the beam within while also providing protection against debris, impact, precipitation, etc.
In one or more embodiments of the invention, a collapsible generator frame design can be used to reduce the overall size or footprint of a non-rotating wind energy generator. A collapsible frame can optionally fold, slide, and/or disassemble to reduce overall size or footprint.
In one or more embodiments of the invention, the top surface of the frame is curved and sufficiently covers the beam and other system components in order to shield them from precipitation and falling debris.
In one or more embodiments of the invention, multiple generator systems can be stacked vertically or horizontally and held together by brackets, magnetic attraction, or other means to form an array. The flow of electricity from one individual generator system to another or to single outlet can be facilitated by the use of electrical plugs and jacks or electrically conductive magnetic surface contact. A modular system of generators allows for greater overall power output to be achieved.
In one or more embodiments of the invention, bumpers can be mounted to the frame to reduce or stop over-amplification of the oscillatory motion of the beam. The location and size of the bumper can be selected to permit the largest amplitude possible before the individual coils of the extension springs suspending the beam are compressed far enough to touch each other. Preventing the springs from reaching their fully unstretched state helps minimize undesired impact stresses on the springs and also eliminates associated impact noise. The use of low-density foam, rubber, compression springs, fabric, rubber bands, or other material or method of impact dampening can be utilized. Such material or method can have satisfactory cyclic fatigue life and be unaffected by environmental conditions.
In one or more embodiments of the invention, opposing magnets can be utilized to apply the necessary damping force. One set of magnets can be mounted to a horizontal member of the frame and another can be mounted to the top or bottom face of the beam (across from the stationary set). Sides of the magnets with the same polarity can face each other and apply a repulsive force when the magnet proximity is close.
In one or more embodiments of the invention, the concepts of eddy currents, Lenz's Law, or a combination of both can be utilized to apply a damping force on the beam. Magnetic flux from magnets located on the beam can create eddy currents in electrically conductive materials (e.g. copper and aluminum). These eddy currents can cause a damping force on the beam, which can cause the beam to slow and not exceed the desired maximum amplitude. One or more electromagnetic coils can be located at or near the desired maximum amplitude of beam motion. The ends of the coil can be joined together to create a short circuit that can apply a maximum damping force on the beam. Additionally, a segment of copper or aluminum block or sheet metal can be used to induce a damping effect.
In one or more embodiments of the invention, an array of more than two extension springs can be mounted along the top and bottom of beam. The use of multiple springs has the benefit of reducing the cyclic stresses encountered by each spring, thus improving their overall fatigue life. Multiple springs can also serve to add extra stability to beam motion. Mixing springs of differing stiffness can result in greater variability of overall effective spring stiffness for the system. This can allow better tuning of this variable to meet specific design requirements.
In one or more embodiments of the invention, the mounting locations of the ends of the extension springs are located in close proximity to the central horizontal axis of the beam. Mounting at this location on the beam can allow the beam to oscillate at the highest amplitude within a frame of shortest vertical height for a given spring. Increasing the amplitude of oscillations can result in faster relative velocity of the magnets and coils, and thus higher electrical power generation.
In one or more embodiments of the invention, the springs are stretched and mounted to the top and bottom horizontal support members of the frame. The beam can be secured onto the extension springs by attaching to the coils in the middle of the stretched spring directly (as opposed to the hooks located at the ends of most extension springs). The use of this arrangement and mounting method can have the benefit of reducing the unstretched spring length that factors into the overall height of the frame by half [Overall Frame Height=(2×unstretched spring length)+(distance between spring mounting location on beam)+(desired peak to peak beam oscillation amplitude)]. This reduction can allow for a smaller frame height or higher beam amplitude within a given frame size (whichever is desired). Additional benefits of this embodiment can include cost savings due to the use of fewer springs and improvements in lateral motion stability of the beam (in the direction perpendicular to the beam oscillation and perpendicular to the front face of the beam). Mounting to the coils of the spring as opposed to the hooks can improve spring fatigue life due to reduced tensile stress on the wire near the hook locations.
In one or more embodiments of the invention, extension springs can be secured to the generator's frame and movable beam by a bracket that engages with one or more coil turns of the helical spiral. Eliminating spring hooks can reduce overall system height and increase maximum amplitude of beam oscillation and reduce manufacturing cost and complexity.
In one or more embodiments of the invention, the springs used to elastically mount the movable beam are coated in a layer of plastic, rubber, or other material to protect and minimize the effect of precipitation and debris—thus reducing corrosion and improving lifespan.
In one or more embodiments of the invention, multiple permanent magnets can be mounted to beams in a location where their magnetic field lines intersect electromagnetic coils in close proximity, as shown, for example, in
In one or more embodiments of the invention, one or more magnets and electromagnetic coils can be axially aligned such that the magnet passes in and out of a cylindrical opening in the center of the coil as the beam oscillates. One or more permanent magnets can be fixed to the elastically mounted beam while the electromagnetic coils are fixed stationary to some portion of the frame. One or more electromagnetic coils can also be fixed to the elastically mounted beam while one or more permanent magnets are fixed stationary to some portion of the frame. Additionally, one or more coils having a cylindrical opening can be mounted to the beam and one or more magnets can be mounted to the frame such that the magnet passes in and out of a cylindrical opening in the center of the coil as the beam oscillates. The relative motion of the magnets and coils causes a change in magnetic flux through the coils that results in electricity generation.
In one or more embodiments of the invention, the electrical energy output of the wind generator system can be conditioned by an electrical circuit known as the Cockcroft-Walton (CW) multiplier (also referred to as the Greinacher multiplier, voltage multiplier, or voltage doubler/tripler). This circuit is capable of generating high DC voltage from a low voltage AC input. In the application of non-rotating wind energy generators, this circuit can serve multiple purposes including AC to DC rectification, voltage output multiplication/boosting, suppression of electrical load damping effect that hampers beam oscillations. The overall benefit of the use of this circuit can include boosting low voltage AC output to a higher voltage DC output, high rectification and boosting efficiency, improved beam motion performance in low fluid flow velocities due to decreased damping effects, and decreased circuit cost due to simple, widely available, inexpensive components and construction.
In one or more embodiments of the invention, the input voltage to output voltage can be doubled, tripled, quadrupled, and further multiplied by incorporating additional diode and capacitor components in stages to achieve the desired electrical characteristics.
In one or more embodiments of the invention, the input voltage to the voltage multiplier circuit can be AC generated by one or more magnets passing by one or more electromagnetic coils. Multiple coils can be wired in series. Additionally, the coils can be wired in parallel.
In one or more embodiments of the invention, the electrical energy generated and conditioned by the voltage multiplier circuit can be stored in a rechargeable battery. Rechargeable battery types include but are not limited to Nickel-metal hydide (NiMH), Nickel-cadmium (NiCd), and Lithium-ion polymer (LiPo).
In one or more embodiments of the invention, the electrical energy generated and conditioned by the voltage multiplier circuit can be stored in a supercapacitor (also known as an ultracapacitor).
In one or more embodiments of the invention, the wind generator can be used to provide electricity to one or more LED's to provide illumination, signals, or signage. In the event that the voltage of the energy storage device (e.g. a single 1.2V rechargeable NiMH battery) is insufficient to directly illuminate an LED (which can use between 1.6-4.0V, depending on color and type), a DC-DC boost converter (step-up converter) circuit can be used to boost the output voltage to the required level for LED operation. In light load/low power applications, an integrated circuit LED driver chip or a boost converter circuit known as a blocking oscillator or “Joule Thief” can be used as an LED driver. Such embodiments can also include dark activated switches to detect darkness and activate the LED when light levels are low.
In one or more embodiments of the invention, solar panels can be affixed to the non-rotating wind energy generator system to form a hybrid energy harvesting system. This hybrid system permits the harvesting of multiple sources of ambient energy and aids in maintaining some minimum level of electrical energy generation for use by a given application. The wind subsystem can continue to provide energy generation during periods of low light and the solar subsystem can continue to provide energy generation during periods of low wind if those sources of ambient energy are available. The solar panels are optionally affixed to the top, front, back, and side faces of the frame. The panels can be mounted on pivots to allow for adjustability of the angle of the panel relative to the sun for maximum light exposure. The energy from the solar and wind generator subsystems can be collected and stored in a common storage device (e.g. rechargeable battery or supercapacitor) before use or in separate storage devices.
It will be appreciated that while a particular sequence of steps has been shown and described for purposes of explanation, the sequence may be varied in certain respects, or the steps may be combined, while still obtaining the desired configuration. Additionally, modifications to the disclosed embodiment and the invention as claimed are possible and within the scope of this disclosed invention.
In a further aspect of the invention, a non-rotating wind energy generating apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy, using self-excited oscillation caused by vortex shedding, transverse galloping, or some combination thereof, and an inductor system, also referred to as a linear alternator system, operable to generate electrical energy via the motion of the suspended bluff body.
In a further aspect of the present invention, exposing the non-rotating wind energy generating apparatus of any of the proceeding embodiments to wind generates oscillatory motion in response to wind energy using self-excited oscillation caused by vortex shedding, transverse galloping, or some combination thereof, and generates electrical energy via motion of the non-rotating wind energy generating apparatus using electromagnetic induction.
Aspects of this invention relate to a novel approach to harnessing wind power. In an embodiment of the invention, the device uses the fluid flow principle of vortex shedding and transverse galloping to generate oscillatory, linear motion of a beam. In an embodiment of the invention, linear alternators optionally located near both ends of the beam generate electrical power when the beam is in motion.
In an aspect of the invention, a non-rotating wind energy generating apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy and a linear alternator system operable to generate energy via the motion of the suspended bluff body. In one or more embodiments, the suspended bluff body may comprise a frame movably supporting at least one beam, one or more first springs, one or more second springs, wherein the one or more first springs attach a first portion of the frame to a first portion of the beam and the one or more second springs attach a second portion of the frame to a second portion of the beam such that the beam is suspended between the first and second portions of the frame, and wherein the linear alternator system comprises at least one electromagnetic coil attached to one of the beam or a third portion of the frame, at least one magnet attached to one of the third portion of the frame or the beam, wherein motion of the beam when exposed to wind causes the first inductor to pass the at least one magnet. In any of the proceeding embodiments, the beam may have a D-shape. In any of the proceeding embodiments, the beam may be hollow. Any of the proceeding embodiments may further comprise one or more motion guides. Any of the proceeding embodiments may further comprise one or more additional beams, one or more additional upper springs, one or more additional lower springs, wherein the one or more additional upper springs attach a first portion of the additional beam to a third portion of the beam and the one or more additional lower springs attach a second portion of the additional beam to a fourth portion of the beam such that the one or more additional beams are suspended between the first and second portions of the frame. In any of the proceeding embodiments, the first portion of the frame may be an upper portion, the first portion of the beam may be an upper portion, the second portion of the frame may be a lower portion, and the second portion of the beam may be a lower portion. In any of the proceeding embodiments, the third portion of the frame may be a side portion. In any of the proceeding embodiments, the beam may be suspended substantially horizontally. In any of the proceeding embodiments, the motion of the beam may be substantially vertical. In any of the proceeding embodiments, a surface of the beam may be uniformly smooth. In any of the proceeding embodiments, a surface of the beam may be partially smooth. In any of the proceeding embodiments, a surface of the beam may be uniformly rough. In any of the proceeding embodiments, a surface of the beam may be partially rough. In any of the proceeding embodiments, at least one electromagnetic coil or the at least one magnet may be attached to a first end of the beam. In any of the proceeding embodiments, the spring stiffness may be selected to promote self-oscillatory motion. In any of the proceeding embodiments, the beam may have a cross-sectional geometry selected from the group consisting of a square, a cylinder, a reversed D-Beam (where the wind is primarily incident on the round portion of the beam rather than the flat portion), and an equilateral wedge in either a “greater than” or “less than” orientation relative to the incident wind. In any of the proceeding embodiments, the springs may be stretched in a resting state. In any of the proceeding embodiments, the beam mass may be selected to promote self-oscillatory motion. In a further aspect of the present invention, exposing the non-rotating wind energy generating apparatus of any of the proceeding embodiments to wind generates oscillatory motion in response to wind energy using vortex shedding, transverse galloping, or some combination thereof, and generates electrical energy via motion of the non-rotating wind energy generating apparatus using electromagnetic induction.
Further aspects of the invention relate to non-rotating wind energy generating apparatuses where a central axis of the at least one electromagnetic coil is substantially parallel to a longitudinal axis of the beam. In an embodiment of the invention, the at least one magnet is positioned relative to the at least one electromagnetic coil such that the beam when exposed to wind causes an electromagnetic coil to pass the at least one magnet generating electrical power.
In a further aspect of the invention, a non-rotating wind energy generating apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body. In a further aspect of the invention, the suspended bluff body comprises a frame movably supporting at least one beam, the linear alternator system comprises at least one electromagnetic coil and at least one magnet, a central axis of the at least one electromagnetic coil is substantially parallel to a longitudinal axis of the beam, and the at least one magnet is positioned relative to the at least one electromagnetic coil such that motion of the beam when exposed to wind causes the first electromagnetic coil to pass the at least one magnet. In one or more embodiments, the at least one electromagnetic coil is attached to one of the beam or a third portion of the frame and the at least one magnet is attached to one of the third portion of the frame or the beam. In any of the proceeding embodiments, at least one electromagnetic coil can be spaced apart from the at least one beam by a mounting bracket. In any of the proceeding embodiments, the mounting bracket can position a central axis of the at least one electromagnetic coil along the same longitudinal axis as the central axis of the at least one beam. In any of the proceeding embodiments, the at least one magnet can be positioned in a space provided between the at least one electromagnetic coil and the beam. In any of the proceeding embodiments, at least one electromagnetic coil can extend beyond a face of the at least one beam. In any of the proceeding embodiments, at least one electromagnetic coil can be attached to the at least one beam and the at least one magnet can be attached to the frame. In any of the proceeding embodiments, at least one electromagnetic coil can be attached to the frame and the at least one magnet can be attached to the at least one beam.
Further aspects of the invention relate to non-rotating wind energy generating apparatuses where a linear alternator system comprises at least one electromagnetic coil attached to one of the beam or the frame and two or more pairs of magnets. In an embodiment of the invention, an electromagnetic coil passes through magnetic fields generated by the pairs of magnets generating electricity.
In a further aspect of the invention, a non-rotating wind energy generating apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body, and the linear alternator system comprises at least one electromagnetic coil attached to one of the beam or the frame and two or more pairs of magnets. Additionally, in a further aspect of the invention, the two or more pairs of magnets are attached to one of the frame or the beam, and the at least one electromagnetic coil passes through magnetic fields generated by the two or more pairs of magnets. In one or more embodiments of the invention, a first side of a first magnet of a first pair of magnets faces a first side of a second magnet of the first pair of magnets, wherein the first side of the first magnet of the first pair of magnets has a polarity of North or South and the first side of the second magnet of the first pair of magnets has a polarity of North or South, wherein the polarity of the first side of the first magnet of the first pair of magnets differs from the polarity of the first side of the second magnet of the first pair of magnets, and wherein a first side of a first magnet of a second pair of magnets faces a first side of a second magnet of the second pair of magnets, wherein the first side of the first magnet of the second pair of magnets has a polarity of North or South and the first side of the second magnet of the second pair of magnets has a polarity of North or South, wherein the polarity of the first side of the first magnet of the second pair of magnets differs from the polarity of the first side of the second magnet of the second pair of magnets. In any of the proceeding embodiments, the polarity of the first side of the first magnet of the first pair of magnets can differ from the polarity of the first side of the first magnet of the second pair of magnets and the polarity of the first side of the second magnet of the second pair of magnets can differ from the polarity of the first side of the second magnet of the first pair of magnets. In any of the proceeding embodiments, a first side of a first magnet of a third pair of magnets can face a first side of a second magnet of the third pair of magnets, wherein the first side of the first magnet of the third pair of magnets can have a polarity of North or South and the first side of the second magnet of the third pair of magnets can have a polarity of North or South, wherein the polarity of the first side of the first magnet of the third pair of magnets can differ from the polarity of the first side of the second magnet of the third pair of magnets. In any of the proceeding embodiments, the polarity of at least one of the first side of the first magnet of the first pair of magnets, the first side of the first magnet of the second pair of magnets, and the first side of the first magnet of the third pair of magnets can differ from the polarity of at least one of the first side of the first magnet of the first pair of magnets, the first side of the first magnet of the second pair of magnets, and the first side of the first magnet of the third pair of magnets.
Further aspects of the invention relate to non-rotating wind energy generating apparatuses wherein the linear alternator system comprises at least one electromagnetic coil inset into one of a beam or a frame and at least one magnet inset in one of the frame or the beam. In an embodiment of the invention, motion of the beam when exposed to wind causes the at least one electromagnetic coil to pass at least one magnet generating energy.
In a further aspect of the invention, a non-rotating wind energy generating apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body. In a further aspect of the invention, the suspended bluff body comprises a frame movably supporting at least one beam. Additionally, in a further aspect of the invention, the linear alternator system comprises at least one electromagnetic coil inset into one of the beam or the frame and at least one magnet inset in one of the frame or the beam, and a central axis of the at least one electromagnetic coil is substantially parallel to a longitudinal axis of the beam and motion of the beam when exposed to wind causes the at least one electromagnetic coil to pass at least one magnet. In one or more embodiments of the invention, the at least one electromagnetic coil is inset in the at least one beam and the at least one magnets is inset in the third portion of the frame. In one or more embodiments of the invention, the at least one electromagnetic coil is inset in the third portion of the frame and the at least one magnets is inset in the at least one beam.
Further aspects of the invention relate to a non-rotating wind energy transmission apparatus and method. In an embodiment of the invention, each of the two wire leads from each of the electromagnetic coils connect to a spring for electricity transmission and separate wire leads connect to each of the springs at the location of contact between the springs and the frame to continue the transmission of electricity from the springs to a preferred point of use.
In a further aspect of the invention, a non-rotating wind energy transmission apparatus comprises a suspended bluff body operable to initiate and sustain oscillatory motion in response to wind energy and a linear alternator system operable to generate electrical energy via the motion of the suspended bluff body. In a further aspect of the invention, the suspended bluff body comprises a frame movably supporting at least one beam. Additionally, in a further aspect of the invention, the linear alternator system comprises at least one electromagnetic coil attached to one of the beam the frame and at least one magnet attached to one of the frame or the beam. Also, in a further aspect of the invention, motion of the beam when exposed to wind causes the at least one electromagnetic coil to pass at least one magnet and a first wire lead from the at least one electromagnetic coil is connected to at least one of the one or more first springs and a second wire lead from the at least one electromagnetic coil is connected to the other of the at least one of the one or more second springs. In one or more embodiments of the invention, a third wire lead from at least one of the one or more first springs can be connected to the first portion of the frame and a fourth wire lead from the other of the at least one of the one or more second springs can be connected to the second portion of the frame. In any of the proceeding embodiments, the first and second portions of the frame are configured for transmission of electricity from the first and second springs to one or more points of use.
Further aspects of the invention relate to a method for electricity transmission comprising generating electricity using an apparatus according to any of the embodiments described above and transmitting electricity from one or more wire leads of the one or more springs to the frame.
Embodiments of the invention convert kinetic energy of an oscillating bluff body (e.g., a beam driven by fluid flow phenomena) into electrical energy via electromagnetic inductor.
In embodiments of the invention, coils of wire are located at the ends of an oscillating bluff body (e.g., beam) and the flat face of the wire coils is parallel to the front flat face of the beam. The central axis of the coil can be perpendicular to the central axis of the beam.
In embodiments of the invention, coils of wire attached to an oscillating bluff body can pass through a single pair of magnets that have poles (North, South) that face each other.
In embodiments of the invention, multiple pairs of magnets can be positioned in specific arrangements. Such embodiments can have improved kinetic energy to electrical energy conversion. For example, multiple pairs of magnets can be positioned above and below other pairs of magnets such that as the bluff body (e.g., a beam) carrying the coils travels up and down, the coils pass through several magnetic fields generated by the parallel magnets. In an embodiment of the invention, the relative polarity of each stacked magnet pair is reversed (North, South, North, South, etc.). In at least one embodiment of the invention, the change in magnetic flux direction that the coil of wire experiences as the bluff body (e.g., beam) oscillates has a significant improvement in electrical energy conversion/generator power output. A gap of any distance between adjacent pairs of magnets may or may not be present.
In alternate embodiments of the invention, the coil of wire can be located at the ends of oscillating bluff body (e.g., beam) with their flat face perpendicular to the front face of the beam. The central axis of the coil can be parallel to the central axis of the beam. In at least one such embodiment, lateral motion of the bluff body caused by excessive wind forces acting on the front face of the beam will not cause the beam to come in contact with the magnet holders, guide plate, or any other surface. In an embodiment of the invention, the coils can be mounted on extended “U-shape” mounting brackets to permit them to pass through one or several sets of parallel magnets. The “U-shape” mounting bracket can position the center of mass of the coils of wire in the same plane as the center of mass of the beam. In certain embodiments, this can provide improved stability.
In further alternate embodiments, the coils can be extended beyond the front face of the bluff body (e.g., beam). In these further alternate embodiments, the center of mass of the coils is not in the same plane as the center of mass of the beam.
In a further aspect of the invention, electricity is transmitted from a generation source located onboard a moving bluff body (e.g., a beam) to a terminal statically located elsewhere on a non-rotating wind energy generator (NRWEG). In certain embodiments of the invention, the embodiment may advantageously permit the transmission of electricity from the generation source located on a moving bluff body (e.g., a beam) to a static terminal location without the need for additional wire leads or points of contact. In certain embodiments of the invention, the springs used to suspend the bluff body (e.g., a beam) may advantageously act as wire leads that conduct electricity from the electromagnetic coils that are mounted onboard the moving bluff body (e.g., beam).
By using springs as leads for electricity transmission, the need for additional wires or points of contact can be reduced or eliminated. This can reduce the drag force on a beam due to mechanical friction from rubbing contact or periodic flexing of separate wire leads. The use of spring wire leads can also be more cost effective, reliable, and less susceptible to failure.
Aspects of the invention related to electricity transmission have significant economic potential when paired with aspects of the invention related to non-rotating wind energy generator systems. For most or all commercial applications of embodiments of non-rotating wind energy generator systems, aspects of the invention related to electricity transmission could be used for efficient operation/power generation.
In an embodiment of the non-rotating wind energy generator (NRWEG) apparatus, electromagnetic coils are mounted to a bluff body (e.g., a beam) that is suspended by springs. In this embodiment, during operation, airflow passes over the bluff body and causes it to oscillate rapidly. As the bluff body oscillates in this embodiment, the electromagnetic coils pass through magnetic fields formed by permanent magnets statically mounted to the NRWEG frame. When this occurs, electricity can be generated in the electromagnetic coils. To effectively use this electricity, it can be transmitted from the electromagnetic coils to a statically mounted terminal location. An effective method for electricity transmission can include using the springs as electrical leads. To do this, each of the two wire leads from the electromagnetic coil can be connected (e.g., via solder, clip, screw, etc.) to one of the springs that is used to suspend the bluff body. The other end of the spring can be mounted to some portion (e.g., the top and bottom horizontal members) of an NRWEG frame. A separate wire lead can be connected to each of the springs (at the location of contact between the spring and frame) to continue the transmission of electricity from the springs to the preferred point of use (e.g., terminal box, power conditioning circuitry, etc.).
The present application claims the benefit of U.S. Provisional Patent Application No. 61/863,571, filed on Aug. 8, 2013 entitled “Electrical Power Monitor and Control System for a Non-Rotating Wind Energy Generator,” the content of which is hereby incorporated by reference herein in its entirety. Additionally, the present application claims the benefit of U.S. Provisional Patent Application No. 61/863,602, filed on Aug. 8, 2013 entitled “Flat Spring Bluff Body Oscillator for Wind Energy Harvesting,” the content of which is hereby incorporated by reference herein in its entirety. Additionally, the present application claims the benefit of U.S. Provisional Patent Application No. 61/863,900, filed on Aug. 8, 2013 entitled “Novel Magnet And Coil Inductor Configurations For A Non-Rotating Wind Energy Generator,” which is herein incorporated by reference in its entirety. Additionally, the present application claims the benefit of U.S. patent application Ser. No. 14/054,820, filed on Oct. 15, 2013 entitled “Non-Rotating Wind Energy Generator,” which is herein incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US14/49317 | 7/31/2014 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 61863900 | Aug 2013 | US | |
| 61863602 | Aug 2013 | US | |
| 61863571 | Aug 2013 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14054820 | Oct 2013 | US |
| Child | 14911016 | US |
