Title: Expander/Compressor/Pump for a Solar Thermal AC System, USA
A solar thermal AC system consists of a Rankine power cycle and vapor-compression refrigeration cycle. It is operated by a combination expander/compressor/pump unit (ECP).
We used a NI USB-6353 X series DAQ, a NI USB-6009 series DAQ, and LabVIEW.
The challenge is to operate the ECP unit using solenoid valves and record pressure and position data over time.
The ECP is operated using a VI that controls the opening of the solenoid valves based on input from a position sensor attached to the piston rod. Data can be recorded from five pressure transducers located in the expander (2), compressor (2), and pump (1).
Using LabVIEW has allowed us to control the operation of the expander. The high pressure can be “cut-off” part way through the stroke to allow the gas to expand and increase efficiency.
This is the actual ECP unit running with our LabVIEW controls.