A refined classification method of heat customers to improve inter-household thermal balance intelligent control and regulation

Hydraulic imbalance in district heating systems (DHSs) especially in the secondary pipe network hinders the improvement of system energy efficiency. To improve inter-household thermal balance on the secondary side, this paper proposes a refined classification and intelligent regulation method for heat customers. Firstly, an intelligent balancing system is proposed with the smart valves installed at heat customer's thermal entrance. Then, the refined method classifies the heat customers based on room comprehensive thermal characteristic coefficient. The regulation periods and target return temperature predictive models are determined for each customer type to achieve balance regulation. Finally, the proposed intelligent balance system was applied to a practical DHS secondary pipe network to verify its balance effect. After the regulation, indoor temperature non-uniformity coefficient for each type of heat customer decreased by 15 %; while the return water temperature dispersion reduced by 8 %–18 %. This led to a significant improvement in hydraulic and thermal balance among heat customers, resulting in a 6.2 % heat-saving rate. The application provides a reference for inter-household thermal balance regulation in scenarios where indoor temperature loggers are limited within similar secondary pipe network of DHSs.