A user-friendly tool for the integrated simulation of building HVAC control performance

Full simulation of a building’s HVAC control is important. Good control is the most cost-effective way to reduce plant size and save energy and maintenance cost. To address these issues the control designer needs an easy to use, but accurate tool that simultaneously solves the building thermal, the HVAC system and its control performance. We have developed such a tool. Our new simplified, yet extensively verified, building model made an efficient integrated tool possible. The system simulation is also done using simplified yet accurate component models. A unique simulation tool resulted. Any building, any HVAC system and any control strategy can now easily be built up using a graphical user interface. The system is then iteratively solved by obtaining an energy balance for each component and for the system as a whole. The software was already successfully verified against eight case studies. The results proved to be sufficiently accurate for design as well as control and energy analyses. For example, energy predictions are generally within 10% of measured values while zone temperatures are within 1 oC for 90% of the time. A new user typically takes one day to use the software. Computing time for a very involved building, HVAC system and complex energy management control is approximately 10 minutes on a PC. It is thus easy and practical to investigate various control strategies.