A new pattern recognition adaptive controller with application to HVAC systems

This paper describes a novel method for automatically adjusting the gain and integral time of proportional-integral controllers based upon patterns that characterize the closed-loop response. The method was developed for self-regulating systems that can be modeled as first-order plus dead-time systems. This new pattern recognition adaptive controller (PRAC) is easy to use and provides near-optimal performance for a range of systems and noise levels. Also, the algorithm is computationally efficient and does not have large memory requirements. PRAC has successfully tuned control systems for heating, ventilating, and air-conditioning (HVAC) equipment in office buildings, high schools, universities, national laboratories, department stores, hospitals, clinics, and large sports stadiums. Simulation and field test results are included in this paper. (C) 1998 Elsevier Science Ltd. All rights reserved.