Study on the Control Strategy and Algorithm of Cooling Source Based on Cooling on Demand in Intelligent Building Management

From the idea of unified energy management, this paper analyzed the composition and the energy saving ways of the cooling source in intelligent building, established the applicable chiller plant control algorithmic modules on the basis of the innovative control strategy of cooling on demand and the control module library. Study focused on the optimized control algorithms of the chilled water supply temperature set-point control according to the cooling request on demand, the chiller operating numbers and proper operating order and running cycle control, and the chilled water pump frequency conversion control according to the cooling request on demand. The feasibility and stability was tested and verified in the laboratory. The ideal effects were also achieved in a practical project in Ningxia Hui autonomous region, China. The results show that the system can be loaded/unloaded efficiently, and the fluctuation of water temperature at the chiller´s outlet around the setpoint remains quite small, which reflect very good control precision and notable energy-saving effects.