Embodiments relate to valves comprising a member such as a plate or poppet, that is moveable relative to a stationary seat. The state of the member may be maintained against opposing forces with relatively little expenditure of energy. According to one embodiment, a poppet displaced from seating in the valve seat, may be held in position against opposing forces tending to close the valve, until a desired flow of gas through the valve has taken place. The poppet may then be released as desired, such that those opposing forces serve to passively close the valve. The valve may be secured in position utilizing mechanical, magnetic, electromagnetic, pneumatic, electrostatic, or hydraulic approaches. Valve embodiments may be particularly suited to controlling gas flows for compression and/or expansion in an energy storage system.
1. An apparatus comprising:
a cylinder configured to receive a piston and defining a first port;
a mechanical linkage comprising a piston rod configured to transmit out of the cylinder, a power of gas expanding against the piston;
an element configured to effect gas-liquid heat exchange with gas in the cylinder in an absence of combustion; and
a first valve comprising,
a first valve element moveable relative to the first port,
a second valve element selectively rotatable relative to the first valve element to control a duration of opening of the first port, and
a third valve element selectively moveable to control a starting point of opening of the first port.
2. An apparatus as in claim 1 further comprising an actuator in communication with the third valve element.
3. An apparatus as in claim 2 wherein the actuator comprises a stepper motor.
4. An apparatus as in claim 2 wherein the actuator is in communication with the third valve element via a rotating shaft.
5. An apparatus as in claim 4 wherein the rotating shaft is in communication with a gear.
6. An apparatus as in claim 4 wherein the rotating shaft comprises a pinion shaft.
7. An apparatus as in claim 1 wherein the first valve further comprises a spring.
8. An apparatus as in claim 1 wherein the first valve further comprises a pivot arm.
9. An apparatus as in claim 1 wherein the second valve element comprises a plate.
10. An apparatus as in claim 1 wherein the third valve element comprises a plate.
11. An apparatus as in claim 1 further comprising a physical connection to coordinate actuation of the first valve with the piston.
12. An apparatus as in claim 11 wherein:
the mechanical linkage further comprises a crankshaft; and
the physical connection comprises a gear off the crankshaft.
13. An apparatus as in claim 12 wherein the gear is phase displaceable.
14. An apparatus as in claim 1 further comprising a control system comprising a Variable Frequency Oscillator (VFO) and configured to control a timing of the first valve.
15. An apparatus as in claim 1 further comprising a control system configured to control a timing of the first valve to determine a volume of gas for expansion in the cylinder.
16. An apparatus as in claim 1 further comprising a control system configured to control a timing of the first valve based on a sensed parameter.
17. An apparatus as in claim 1 further comprising a control system configured to control a timing of the first valve based on a phase lock loop.
18. An apparatus as in claim 1 wherein the first valve is actuable to place the cylinder in fluid communication with a high pressure side.
19. An apparatus as in claim 18 wherein the mechanical linkage is in selective communication with an energy source to compress gas within the cylinder.
20. An apparatus as in claim 19 further comprising a control system configured to open the first valve where a built-up pressure in the cylinder nears a pressure on the high pressure side.