Experiences in Applying Adaptive Control to Thermal Processes in Buildings

Application of a self-tuning controller to heating, ventilating, and air-conditioning (HVAC) processes is reported. Adaptive control techniques are attractive in HVAC applications because process characteristics change widely due to variations in weather and building occupancy. Successful implementation of adaptive control techniques is limited by current practices in building instrumentation. Control actuators exhibit significant non-linearities while sensing is inadequate to compensate for load disturbances. A self-tuning control system consisting of an auto-tuner, recursive least squares estimator and a performance monitor is both easily configured and sufficiently robust for unsupervised operation.