A temperature and time-sharing dynamic control approach for space heating of buildings in district heating system

Abstract

Poor indoor temperature control level is the most common issue of building space heating in Chinese district heating system (DHS). The aim of this study was to provide on-demand heating for the buildings. A temperature and time-sharing dynamic control approach was developed by integrating three energy-saving heating patterns. Given that different heating patterns had different set temperatures, unreasonable patterns switching time would cause indoor temperature to deviate from set value. To address this issue, equivalent thermal capacity of building was introduced to establish an indoor temperature prediction model and to determine the appropriate switching time. The practical application of proposed approach was based on the control system with wireless indoor temperature monitoring. A group of buildings with the same demand temperature could be controlled by one control system. A DHS in a university was selected as a case study to validate the proposed method. The experimental works include short-term and long-term validation. Short-term daily comparative experiments showed that the approach could yield heat-saving and heating on-demand for different buildings. Four heating seasons’ long-term operation data indicated the approach could save annual heat use by 14.6%–28.7%. The energy-saving effect also yielded considerable economic and environmental benefits.