Micro environmental control system
A micro environmental control system that can remove or add 30W from or to the near range personal microenvironment of a user. For cooling, the μX uses a micro vapor compression system during the un-occupied period to freeze a phase-change-material in a thermal storage module. A fan then moves air over the phase-change-material to deliver cooled air. Heating is delivered by a small electric heater integrated into a condensing unit. The resulting system is inexpensive to build and uses a limited amount of energy.
1. A micro environmental control system, comprising:
a micro vapor compression system having a compressor, a condenser coupled to the compressor, an expansion valve coupled to the condenser, a reversing valve, and a refrigerant circulating through the micro vapor compression system;
a thermal storage module including a solid-liquid phase change material and an evaporator that is embedded in the solid-liquid phase change material and coupled to the expansion valve;
at least one fan positioned to selectively direct a stream of air through the solid-liquid phase change material or over the condenser; and
a controller coupled to the compressor and the fan that is programmed to operate the micro environmental control system in a cooling mode wherein the compressor is operated to cool the solid-liquid phase change material during a first predetermined time period, and the fan is operated to direct the stream of air through the solid-liquid phase change material during a second predetermined time period.
2. The micro environmental control system of claim 1 , wherein the first predetermined time period is during the night and the second predetermined time period is during the day.
3. The micro environmental control system of claim 2 , further comprising a heater associated with the condenser.
4. The micro environmental control system of claim 3 , wherein the controller is further programmed to operate the micro environmental control system in a heating mode where the fan directs air over the heater.
5. The micro environmental control system of claim 4 , further including a set of dampers associated with the fan to selectively direct the stream of air through the solid-liquid phase change material or over the condenser.
6. The micro environmental control system of claim 1 , wherein the system is configured for operation as a heat pump.
7. The micro environmental control system of claim 6 , wherein the controller is programmed to operate the micro environmental control system in a heating mode wherein the micro vapor compression system operates to freeze the solid-liquid phase change material during a first predetermined operating period of the heating mode while the fan is operated to direct a stream of room air over the condenser, and is programmed to operate the micro vapor compression system in reverse to melt the solid-liquid phase change material during a second predetermined operating period of the heating mode.
8. A method of providing micro environmental control, comprising the steps of:
providing a micro vapor compression system having a compressor, a condenser coupled to the compressor, an expansion valve coupled to the condenser, a reversing valve, and a refrigerant circulating through the micro vapor compression system; a thermal storage module including a solid-liquid phase change material; an evaporator embedded in the solid-liquid phase change material; a fan positioned to selectively direct a stream of air through the solid-liquid phase change material; and
using a controller to operate the unit in a cooling mode by cooling the solid-liquid phase change material during a first predetermined time period, and using the fan to direct the stream of air through the solid-liquid phase change material or over the condenser during a second predetermined time period.
9. The method of claim 8 , wherein the first predetermined time period is during the night and the second predetermined time period is during the day.
10. The method of claim 9 , further comprising the step of providing a heater associated with the condenser as part of the unit.
11. The method of claim 10 , further comprising the step of operating the unit in a heating mode where the fan directs air over the heater.
12. The method of claim 11 , wherein the step of providing a unit further includes providing a set of dampers in the unit that are associated with the fan to selectively direct the stream of air through the solid-liquid phase change material or over the condenser.