Energy savings for a solar heated and cooled building through adaptive optimal control

Abstract

This paper describes a study of the applicability of adaptive and optimal control techniques to the control of heating, ventilating, and air conditioning (HVAC) systems of solar heated and cooled buildings. The suitability of optimal and adaptive concepts is discussed and the selected approach is explained. An integral quadratic cost functional to define optimal performance and an identification process to produce a linearized building model are combined to yield an adaptive linear regulator solution. The building model is described and heating system simulations of three versions of the adaptive optimal controller are reported along with a simulation of a conventional controller for comparison. A nonlinear, open-loop, optimal control simulation is also reported and used to indicate an upper bound on achievable performance. Cooling system simulation results are also reported for an adaptive optimal controller and a conventional controller. Substantial savings in auxiliary energy requirements are demonstrated by the adaptive optimal controllers.