GB2478056A

GB2478056A - Fluid powered generator with additional impulse device

Info

Publication number: GB2478056A
Application number: GB1102811A
Authority: GB
Inventors: Bernard James Hargreaves
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-02-22
Filing date: 2011-02-18
Publication date: 2011-08-24
Also published as: GB201002938D0; GB201102811D0

Abstract

A fluid-powered generator, such as a wind or water powered generator, has a vane assembly 6 rotatable on an axle 1 and an electrical generating device 13 connected to the axle to be driven thereby to produce an electrical output, where an electrically powered impulse device 14, such as a motor, is connected to the vane assembly to maintain its rotation within a desired speed range when the wind or water power is reduced below that necessary to maintain rotation within the speed range. Preferably the vane assembly, the impulse generator and the electrical generating device are mounted on and drivably interconnected with a common axle. The impulse device may comprise at least one rotational first magnet interacting with at least one fixed solenoid 16. Preferably the generator is charges a battery and the impulse device draws power from that battery.

Description

Fluid-powered electrical generator This invention relates to fluid-powered electrical generators, and is particularly although not exclusively concerned with wind-powered generators.

In the interests of efficiency, convenience and avoidance of undue equipment stresses, it is desirable that wind-powered generators should operate continuously at a rotational speed within a set range. However, this can be problematical due to natural fluctuations in wind power.

An object of the invention is to compensate for reductions in fluid power to help maintain rotational speed within a desired range.

According to the invention therefore there is provided a fluid-powered generator having a vane assembly rotatable about an axis, and an electrical generating device connected to the vane assembly to be driven thereby to produce an electrical output, characterised by the provision of an electrically powered impulse device operable to rotate the vane assembly.

With this arrangement, the impulse device can be used to help maintain the rotational speed within a desired range by compensating for reductions in fluid power. Thus, during low wind levels a wind generator can be kept rotating at its normal operational speed. The impulse device can also assist with start up or acceleration of the vane assembly after it has come to rest or has reduced to a low level.

In a preferred embodiment, the impulse device is operable to produce rotational movement about an axis and this axis is preferably coincident or aligned or coaxial with the vane assembly axis. Preferably the electrical generating device is operable to produce the electrical output in response to rotational movement of a component thereof about an axis and preferably this axis is coincident or aligned or coaxial with the vane assembly axis. Thus, the vane assembly, the impulse generator and preferably also the electrical generating device are mounted on and/or are drivably interconnected with a common axle (or shaft).

In a further preferred embodiment the impulse device comprises one or more rotational first magnetic elements arranged to interact with one or more fixed second magnetic elements. At least one of the first and second elements may be one or more solenoids. The electrical power for the impulse device may be derived from a storage battery that may be charged from the electrical generating device.

In a further preferred embodiment the vane assembly may comprise one or more hinged structures having a vane element that cooperates with an abutment structure so that it hinges to, and is maintained in, an operational position at which it resists fluid flow when a front face of the element confronts the fluid flow, and which is free to deflect when a rear face of the element confronts the fluid flow. This arrangement can reduce drag.

It is visualised that the invention will find particular application in the context of a wind-powered generator but it may also find application as a water-powered generator.

The invention will now be described further with reference to the accompanying drawings in which: Fig 1 is a diagrammatic side view of one form of an electrical generator according to the invention; Figure 2 is a diagrammatic sectional view on the line 11-11 of Fig 1; and Figure 3 is a diagrammatic top view of a vane of the arrangement of Fig 1.

As shown in Fig 1, a wind-powered electrical generator unit has an axle 1 rotatably mounted in vertical disposition on bottom and intermediate spaced bearings 2,3. The intermediate bearings may be caged roller bearings and the bottom bearings may be sintered bronze/graphite. At the bottom, the axle 1, and the bottom bearings 2, are mounted on a plate welded to a cruciform support structure 4 made from inverted channel-section members with lifting eyes at remote ends thereof, and radial supporting bars 5 for the intermediate bearings 3. At an upper end of the axle there is mounted an antenna and an anemometer for collection and transmission of wind power information (not shown).

At an upper region of the axle there is drivably connected thereto an assembly 6 of a plurality of horizontal vanes 7 extending radially outwardly from the axle 1 at equally spaced positions around the periphery of thc axle 1. Each vane 7 comprises upper and lower generally flat elements 8,9 interconnected by a hinge joint 10 with a stop or abutment (not shown). As shown in Fig 3, the vanes may have a curved profile. The lower element 9 is biased under gravity to adopt a vertical disposition coplanar with the upper element 8. The stop or abutment maintains this vertical disposition when a front face of the lower element 9 confronts a wind stream. The lower element 9 is free to move away from the wind, to reduce drag, when a rear face of the lower element 9 confronts the wind stream. The vane assembly 6 is coaxial with the axle 1 and causes the axle 1 to rotate when the assembly is exposed to adequate wind power.

Beneath the vane assembly 6, within a domed casing 11 surrounded by a protective wall 12, there is an electrical generating device 13 of conventional form drivably mounted on the axle 1 in coaxial disposition therewith. Rotation of the axle 1 causes a component of the generating device 13 to rotate coaxially therewith and thereby the generator produces an electrical output.

Beneath the generating device 13, within the casing 11, there is an impulse device 14 comprising an assembly of permanent magnets on supports 15 extending radially outwardly from, and fixed to so as to be rotatable with, the axle 1 at equally spaced positions around the periphery of the axle 1. The device 14 also comprises one or more solenoids 16 mounted at fixed positions adjacent to the horizontal rotational path of the permanent magnets. The (or each) solenoid 16 is connected to a power source 17. The power source 17 comprises an electrical storage battery, within the casing 11, that is connected to the electrical generating device 13 via a control unit 18 that is also mounted within the casing 13. The control unit 18 controls charging of the battery 17 and also it controls actuation of the impulse device 14. The impulse device 14 is switched on, when the wind speed falls below a predetermined level, so that the (or each) solenoid 16 is activated to cause the supports 15 with the magnets to move away from the solenoid 16 and thereby cause the axle 1 to rotate, or to accelerate, until its rotational speed is within a predetermined range, as monitored by a rotational sensor connected to the axle 1.

With this arrangement, the impulse device 14 helps to maintain rotation of the vane assembly 6 at a speed in a desired range.

The invention is not intended to be restricted to the details of the above embodiment.

Thus, for example, the generator may be used with water power. The generator may incorporate one or more of the following additional features: A compressor unit for underwater balance of internal components; A dehydrator unit to avoid harmful moisture build up; A vacuum pump unit to allow internal operation in a vacuum; Varying vane design to suit particular requirements; Varying bearing and generator potential output and service and upgrading of dimensions; Dome design and protection, plus servicing arrangement; Horizontal axle (shaft) for special circumstances; Clutch freewheel for wind (or water) only mode; Debris guard for hazardous conditions; Variable base strncture for different site conditions.

Claims

Claims !. A fluid-powered generator having a vane assembly rotatable about an axis, and an electrical generating device connected to the vane assembly to be driven thereby to produce an electrical output, characterised by the provision of an electrically powered impulse device operable to rotate the vane assembly.
2. A generator according to claim 1 characterised in that the impulse device is operable to produce rotational movement about an axis and this axis is coaxial with the vane assembly axis.
3. A generator according to claim 1 or 2 characterised in that the electrical generating device is operable to produce the electrical output in response to rotational movement of a component thereof about an axis and this axis is coaxial with the vane assembly axis.
4. A generator according to any one of claims 1 to 3 characterised in that the vane assembly, the impulse generator and the electrical generating device are mounted on and are drivably interconnected with a common axle.
5. A generator according to any one of claims 1 to 4 characterised in that the impulse device comprises one or more rotational first magnetic elements arranged to interact with one or more fixed second magnetic elements.
6. A generator according to claim 5 characterised in that at least one of the first and second elements may be one or more solenoids.
7. A generator according to any one of claims 1 to 6 characterised in that the electrical power for the impulse device is derived from a storage battery that is charged from the electrical generating device.
8. A generator according to any one of claims 1 to 7 characterised in that the vane assembly comprises one or more hinged structures having a vane element that cooperates with an abutment structure so that it hinges to, and is maintained in, an operational position at which it resists fluid flow when a front face of the element confronts the fluid flow, and which is free to deflect when a rear face of the element confronts the fluid flow.
9. A fluid-powered generator substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.