A study on static pressure reset and instability in variable air volume HVAC systems
This project began with testing five different versions of supply duct static pressure reset strategies that fall into two general categories: Proportional plus Integral control loops, and Trim and Respond control strategies. The testing took place from July 2009 through January 2011 at the Energy Resource Station in Ankeny. During this time, these five experimental control strategies were modified and altered in order to achieve substantial energy savings without unwanted instability. In the end, only one strategy, tiered Trim and Respond, was able to perform as desired by saving energy without displaying unstable behavior or significantly impacting maintenance costs.
The final stage of this project saw the tiered Trim and Respond strategy implemented in the Hixson-Lied building on the Iowa State University campus. This field test resulted in no apparent unstable behavior and savings of 37% per week in fan energy savings alone.