A switched dynamic programming approach towards optimal control of multiple rooftop units

Buildings served by multiple rooftop units (RTUs) are widely prevalent in retail and food industries. Till date, most of such buildings utilize plain feedback or heuristic strategies to determine the RTU operations. We present a switched dynamic programming based approach for scheduling rooftop unit operations in an optimal manner. Using a mid-size restaurant served by multiple RTUs as an example, a switched affine dynamic system model is first presented. The RTU coordination control problem is then formulated as a switched optimal control problem with nontrivial switching cost. A dynamical programming based method is proposed for the solution of the switched optimal control problem, which has reasonable computational complexity and can be implemented as a model predictive control algorithm. The proposed method is evaluated through simulations, and its strengths and limitations are discussed.