Energy collector
The invention provides an energy collector which includes an electrostatic drive to increase the acceleration of a rotor to maximize the proportion of the time at which the collector is able to efficiently generate power.
1. An energy collector for collecting energy from a flow of fluid, the collector having:
one or more inlets for receiving said flow of fluid;
a rotor mounted for rotation;
a turbine mounted on said rotor for receiving fluid flow from at least one of said inlets, to drive said rotor into rotation; and
an electrostatic motor arranged to accelerate the rotor.
2. An energy collector according to claim 1 further comprising one or more additional electrostatic motors, each arranged to accelerate the rotor.
3. An energy collector according to claim 1 wherein the electrostatic motor includes a part provided on a stationary part of the collector which is stationary, a rotor part provided on said rotor, a plurality of conductive electrodes provided on one of the rotor part and the stationary part and one or more insulator portions provided on the other of the rotor part and the stationary part, wherein the rotor part and the stationary part spaced apart from each other such that the electrodes are swept by the one or more insulator portions as the rotor rotates.
4. An energy collector according to claim 3 wherein said one or more insulator portions are each provided with a conductive layer on the opposite side of the insulator portion to that facing the electrodes.
5. An energy collector according to claim 3 wherein the rotor part is provided on an annular outer circumferential edge of the rotor and the stationary part is formed on an annular inner surface of the collector facing the annular outer circumferential edge of the rotor.
6. An energy collector according to claim 5 wherein the one or more insulator portions are provided on the rotor and the plurality of electrodes are provided on the stationary part of the electrostatic motor provided on the stationary part of the collector.
7. An energy collector according to claim 6 wherein the one or more insulator portions is a continuous annulus of insulator material.
8. An energy collector according to claim 3 wherein said plurality of electrodes include one or more positive electrodes and one or more negative electrodes, wherein the electrodes are arranged to be connected to a voltage source, in use, such that the voltage applied to the positive electrodes is positive relative to the voltage applied to the negative electrodes.
9. An energy collector according to claim 8 wherein each electrode tapers towards a tip portion of the electrode arranged nearest the insulator portions and each tip points at least partially in a direction offset from the radial direction.
10. An energy collector according to claim 8 wherein the rotor part is provided on an annular outer circumferential edge of the rotor and the stationary part is formed on an annular inner surface of the collector facing the annular outer circumferential edge of the compressor.
11. An energy collector according to claim 8 wherein:
the rotor has at least one end portion having a generally cylindrical outer profile with an axially facing rotor end face;
the rotor part is provided on at least the end portion of said rotor;
the stationary part has at least one end portion having a generally cylindrical outer profile with an axially facing end face opposing the end face on the rotor end portions;
and the stationary part is provided on at least the end portion of said stationary part.
12. An energy collector according to claim 3 wherein:
the rotor has at least one end portion having a generally cylindrical outer profile with an axially facing rotor end face;
the rotor part is provided on at least the end portion of said rotor;
the stationary part has at least one end portion having a generally cylindrical outer profile with an axially facing end face opposing the end face on the rotor end portions;
and the stationary part is provided on at least the end portion of said part.
13. An energy collector according to claim 12 wherein the electrodes are provided on the stationary part and the insulator portions are provided on the rotor part.
14. An energy collector according to claim 12 wherein the rotor part is provided on the turbine.
15. An energy collector according to claim 12 wherein the rotor part is provided on a compressor fan mounted on said rotor.
16. An energy collector according to claim 12 , wherein the rotor part includes a plurality of radially extending angularly spaced elements, the edges of the elements defining said rotor end face.
17. An energy collector according to claim 16 wherein said plurality of angularly spaced elements are formed on the edges of respective fan blades.
18. An energy collector according to claim 12 wherein the stationary part includes a plurality of radially extending angularly spaced elements with spaces between the elements to permit air flow through said stationary part.
19. An energy collector according to claim 18 wherein said plurality of angularly spaced elements are formed on the edges of respective blades.