WO2010094059A1

WO2010094059A1 - Techniques for the maximisation of current output from a bi-directionally driven linear induction generator by enhanced magnetic flux focus and coupling within the magnetic force path

Info

Publication number: WO2010094059A1
Application number: PCT/AU2010/000164
Authority: WO
Inventors: Jason Boyd
Original assignee: Intium Technologies Pty. Ltd.
Priority date: 2009-02-22
Filing date: 2010-02-16
Publication date: 2010-08-26

Abstract

Techniques for achieving the maximisation of current output from a bi- directionally operable electro-magnetic force coupling and transfer system employing flux density optimisation, flux path focus optimisation and precision member coupling alignment to facilitate and intensify the efficiency of conversion from mechanical energy to current flow output.

Description

TECHNIQUES FOR THE MAXIMISATION OF CURRENT OUTPUT FROM A BI-DIRECTIONALLY DRIVEN LINEAR INDUCTION GENERATOR BY ENHANCED MAGNETIC FLUX FOCUS AND COUPLING WITHIN THE MAGNETIC FORCE PATH

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0001] The invention relates to the the maximisation of current output from an electro-magnetic force coupling and transfer system arranged as a linear induction generator by employing flux density optimisation, flux path focus optimisation and precision member coupling alignment to facilitate and intensify the efficiency of conversion from mechanical energy to electrical current output.

DESCRIPTION OF THE PRIOR ART

[0002] The analysis and design of linear motors as converters of electrical energy to physical force output has been well documented, however, whilst various proposals have been mooted for the alternative use of linear induction motors as generators to convert kinetic energy into electrical output, little has been done in practice to advance the state of the art in that field. Industry standard linear motors or generators have poor efficiencies with regard to the conversion of force from external sources to electrical output.

[0003] Prior attempts to apply the principles of linear motor action to convert external acting force to electrical energy include Neuenschwander, US Patent No. 4,539,485 which discloses a system using a rudimentary linear generator to convert energy from the motion of waves in the ocean to electrical energy however the disclosure offers no detail or refinement for the operative mechanism of the generator itself. [0004] Woodbridge, US Patent No. 4,260,901 which discloses a system to convert energy from ocean wave motion using a floating frame and components including "electrical coils" and a "flux producing device" which is made to move vertically between the coils. In an indirect fashion Woodbridge has described a linear generator but without any detail of the component parts or optimisation of the generator itself.

[0005] Tu et al., US Patent No. 7,573,163 which discloses a linear generator employing the elements of a standard linear accelerator design similar to the propulsion techniques used for magnetically levitated trains. In the system proposed by Tu et al. a permanently magnetic structure is specified to consist of a plurality of permanent magnets bonded with mating faces having opposing magnetic polarity and where the permanent magnetic structure is either made to move between a series of coils of conducting wire or where a series of coils of conducting wire is made to move past the permanently magnetic structure. Furthermore the whole system is specified to be a very small in scale for generating power for portable devices and intended to generate relatively small electrical power output. The system is said to be cost effective to manufacture.

Problems of the Prior Art

[0006] Prior proposals exist to convert force from kinetic energy to electrical energy by the operation of linear generators; however, all so far proposed are either inefficient, expensive to manufacture, excessively complex or produce only very small amounts of electrical energy.

[0007] Invariably examples of prior art are limited in specific applications. BRIEF SUMMARY OF THE INVENTION

[0008] The invention is directed to a linear generator with a single ultra high strength hollow cylindrically shaped permanently magnetic member bonded in the industry standard manner with Cyanoacrylate adhesive to both and in between two symmetrically and hollow cylindrically shaped magnetically permeable coupling members of high magnetic permeability and with a copper clad solid cylindrically shaped operating core member of high magnetic permeability where the operating core member and the coupling members are separated by a liner sleeve of Teflon and with a number of turns of high purity copper winding wire disposed around the components both between the liner sleeve and the inner surface of the coupling core member and around the outer surface of the coupling core member at specific locations with respect to the moving and fixed components.

BREIF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 shows an exemplary apparatus in cross sectional view with a single operating core member, a single ultra high strength permanently magnetic member, a liner sleeve component and four coils of conducting wire arranged between the components.

DETAILED DESCRIPTION OF THE INVENTION

[0014] Figure 1 shows an exemplary apparatus in a lateral cross-sectional view of an exemplary apparatus where there are disposed a number of windings (203), (204), (219), (220) of electrically conductive wire about a magnetically permeable coupling member (206) and where the coupling member (206) is optimally magnetically energised from a permanently magnetically charged member (210) which has a magnetic polar orientation with an 'N' type pole (211), and an 'S' type pole (212). The apparatus includes an operating core member of permanently magnetic material (200) with an 'N' type pole (213), and an 'S' type pole (214) arranged with polarisation opposed to that of the permanently magnetically charged member (210). The apparatus is further arranged so as to provide an optimally focussed magnetic flux path from the permanently magnetically charged member (210) through portions of the magnetic coupling member (206) and through the electrically conductive windings (203,(204), (219), (220) to the operating core member (200) as the physical and magnetic alignment of the core member (200) coincides with appropriate sections of the coupling member (206). The apparatus is further arranged so as to accommodate a centrally located chamber formed by a liner membrane (202) where the liner membrane is a material with a low coefficient of friction such as polytetrafluoroethylene, and whereby a permanently magnetically charged operating core member (200) is disposed inside the chamber formed by the liner membrane (202). The liner membrane (202) is constructed to be critically thin in wall thickness to enable precision alignment and magnetic coupling of the operating core member (200) to the coupling member (206), and the operating core member (200) is constructed to be a close tolerance sliding fit inside the liner membrane (202). The apparatus may be configured for force coupling from a single direction by means of arranging one end of the chamber formed by the liner membrane (202) to be closed (221) and the other end of the chamber to be connected through a housing (218) to a port (201) permitting coupling to a force input member or substance. In this configuration a compression spring type member (215) is fixed inside the chamber formed by the liner membrane (202) at the closed end such that one end of the spring type member (215) is fixed to the chamber liner membrane (202) and the other end of the spring type member (215) is in contact with the end of the core operating member (200) such that when the spring type member (215) is uncompressed it will cause the position of the core operating member (200) to be aligned at a mechanical limit barrier (216) which determines the furthermost extreme of the mechanical travel for the operating member (200) away from the closed end of the chamber (221). Another mechanical limit barrier (217) is fixed at the spring end of the apparatus inside the chamber formed by the liner membrane (202) which determines the furthermost extreme of mechanical travel for the operating member (200) toward the closed end of the chamber (221). The spacing of the spring member (215), the liner membrane (202) and the mechanical limit barriers (216) and (217) are configured to control the extent of travel and axial position of the operating core member (200) and thus further optimise the magnetic coupling between operative parts of the apparatus. The apparatus may advantageously be configured for bidirectional force input by means of duplicating the configuration of elements (201) and (218) at both ends of the liner membrane (202) without the liner membrane having a closed end (221), and deleting the element (215). The bi-directional force input arrangement functions with synchronised anti-phase input forces and as such does not require the function of the spring member (215).

[0015] In a preferred embodiment the whole of the apparatus is constructed with all subsections disposed in concentric relationship as in drawing (1) which shows a lateral cross-sectional view. In such an embodiment the permanently magnetically charged member (210), and the permanently magnetically charged core operating member (200) are composed of a very high strength magnetic alloy such as Neodymium-Iron-Boron (NdFeB). The permanently magnetically charged core operating member (200) is additionally clad in a layer of high purity copper to greatly enhance the magnetic coupling from that member. The port end (201) of a centrally located chamber formed by a liner membrane (202) and where the liner membrane is formed of a material such as polytetrafluorethylene is connected to a suitable external input force acting directly and axially on the operating core member (200). When force is applied to one end of the operating core member (200) the core member (200) is caused to move along the core spacing liner membrane (202) and push against the spring member (215). As the pole faces of the operating core member (200) pass through the magnetic flux foci between the faces of the magnetic coupling member (206), electric currents are generated in the electrically conductive windings (203), (204), (219), (220) and power may be drawn from those windings.

[0009] In one embodiment the invention is directed to an assembly where the operating core member receives force directed to one end from the pressure of hydraulic fluid and where the opposite end of the operating core member acts against a helical spring bearing against a fixed part of the structure.

[0010] In another embodiment the invention is directed to an assembly where the operating core member receives force directed to one end from direct mechanical force supplied by a linkage connected to a rotating wheel at a critical radial position where the rotating wheel may be driven by various engines or machines in common use and where the opposite end of the operating core member acts against a helical spring bearing against a fixed part of the structure.

[0011] In yet another embodiment the invention is directed to an assembly where the operating core member receives force directed alternately to each end from the pressure of hydraulic fluid acting directly on the ends of the operating core member and where the alternating nature of the pulses of force from the hydraulic pressure acting on each end accounts for the necessary restoring forces to the operating core member.

[0012] In yet another embodiment the invention is directed to an assembly where the operating core member receives force directed to one end from direct mechanical force supplied by a linkage connected to a rotating wheel at a critical radial position where the rotating wheel may be driven by various engines or machines in common use and where the cyclical movement of the linkage supplies both driving and restoring forces.

[0013] In this way kinetic energy is converted to electricity but with greatly increased efficiency compared to conventional electric generator systems.

[0014] Although the preferred embodiment has been illustrated, it is clear that the invention encompasses other and different arrangements within the scope of the attached claims. [0015] While various embodiments of the present invention have been illustrated herein in detail, it should be apparent that modifications and adaptations to those embodiments may occur to those skilled in the art without departing from the scope of the present invention as set forth in the following claims.

Claims

WHAT IS CLAIMED

1. A linear induction generator comprising a permanently magnetised movable member having force input capability at both ends.

2. Apparatus in claim 1 where the linear induction generator has facility for force input coupling from mechanical means.

3. Apparatus in claim 1 where the linear induction generator has facility for force input coupling from hydraulic means.

4. A linear induction generator comprising: a. a permanently magnetised movable member; and b. a permanently magnetised fixed member.

5. Apparatus in claim 4 where the fixed and movable magnetic members are of high strength.

6. Apparatus in claim 4 where the linear induction generator has facility for force input coupling from hydraulic means.

7. Apparatus in claim 4 where the linear induction generator has facility for force input coupling from mechanical means.

8. A linear induction generator with a copper clad permanently magnetised moving member.