Predictive control for thermal comfort and energy efficiency in a direct expansion air conditioning system

Nowadays, indoor thermal comfort relates closely to both working efficiency of users and energy efficiency of facilities. To achieve an optimal trade-off between working efficiency and energy efficiency, in this paper, a hierarchical model predictive control is proposed for a direct expansion air conditioning (DX A/C) system to control the indoor thermal comfort and energy efficiency simultaneously. The proposed controller is composed by an upper layer optimization to search for the optimal set points, and a lower layer feedback controller such that the optimal set points can be tracked. It can be demonstrated by simulation results that, with the proposed control technique, the closed-loop direct expansion air conditioning system is capable of achieving indoor thermal comfort and energy efficiency simultaneously.