When you study stability of TEV you cannot do it without studying the complete system.

The pair TEV-Evaporator have several characteristic curves, one very important is the Minimum Stable Superheat curve.

You can read about it here:
http://refrignet.asean.danfoss.com/s...=2&Language=en

http://www.ra.danfoss.com/TechnicalI...imitations.pdf

http://www.achrnews.com/Articles/Fea...100000f932a8c0____