A direct load control of air-conditioning loads with thermal comfort control

Abstract

The lack of new generation capacity and the higher fuel generation cost are the serious problems of Taipower. Taipower attempted to make the optimal economic fuel-cost dispatch of its existing generation capacity by applying direct load control method (DLC). However, some constraints such as the outdoor temperature, thermal comfort level of consumers, and air-conditioning load payback phenomenon restrain the executions of DLC. In order to alleviate the above problems, a reasonable DLC program with a least enthalpy estimator (LEE)-based fuzzy thermal comfort controller of air-conditioning systems is proposed in this paper. It can store the heat transfer capacity of the chilled water by a time delay after load-shedding command is issued. With the help of the proposed LEE-based fuzzy control and this pre-stored chilled-water heat transfer capacity, a smaller increase of the chilled-water temperature during off-shift period is obtained which can avoid the transient payback load effect. Meanwhile, the thermal comfort is also maintained within an acceptable level.