Valve
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. A method comprising:
providing a chamber in selective fluid communication with a high pressure side through a first valve comprising a first poppet selectively moveable to disengage from a first seat, wherein the high pressure side is in fluid communication with a compressed gas storage unit;
securing the first poppet disengaged from the first seat against a first countervailing force utilizing a first mechanism;
actively controlling the first mechanism to release the first poppet to engage the first seat while a volume of compressed gas from the high pressure side expands in an absence of combustion within the first expansion chamber to exchange heat with a liquid;
a mechanical linkage comprising a piston rod communicating out of the chamber, a power of the compressed gas expanding against a piston; and
generating from the mechanical linkage an electrical output to meet a load, wherein the first mechanism is actively controlled to maintain the electrical output at a fixed frequency while the load and a gas pressure of the compressed gas storage unit are changing.
2. A method as in claim 1 wherein the mechanical linkage further comprises a crankshaft.
3. A method as in claim 1 wherein the first mechanism is configured to operate based on hydraulic principles.
4. A method as in claim 1 wherein the first mechanism is configured to operate based on mechanical principles.
5. A method as in claim 4 wherein the first mechanism comprises a pin.
6. A method as in claim 4 wherein the first valve comprises a cam-operated poppet valve.
7. A method as in claim 6 wherein a timing of the first valve is controlled by varying an effective cam profile.
8. A method as in claim 6 wherein the first valve further comprises a spring.
9. A method as in claim 1 wherein the chamber comprises one stage of a multi-stage apparatus, and a low pressure side is in fluid communication with another stage.
10. A method as in claim 1 wherein the controlling references a variable frequency oscillator (VFO).
11. A method as in claim 1 wherein the controlling is according to a phase lock loop (PLL).
12. A method as in claim 1 further comprising:
providing the chamber in selective fluid communication with a low pressure side comprising another stage through a second valve comprising a second poppet selectively moveable to disengage from a second seat;
securing the second poppet disengaged from the second seat against a second countervailing force utilizing a second mechanism; and
controlling the second mechanism to release the second poppet to engage with the second seat and retain expanded gas within the chamber.
13. A method as in claim 12 wherein the second mechanism is configured to operate based on hydraulic principles.
14. A method as in claim 12 wherein the second mechanism is configured to operate based on mechanical principles.
15. A method as in claim 14 wherein the second mechanism comprises a pin.
16. A method as in claim 14 wherein the second valve comprises a cam-operated poppet valve.
17. A method as in claim 16 wherein a timing of the second valve is controlled by varying an effective cam profile.
18. A method as in claim 16 wherein the second valve further comprises a spring.