Optimization of group control strategy and analysis of energy saving in refrigeration plant

Abstract

This study proposes a group control system optimization strategy coupled with a refrigeration plant model for a primary pump variable flow system, in order to improve the automation level of the refrigeration plant and maximize the energy saving potential. First, the control variables, optimization objectives, and operational constraints of the entire system were analyzed. Then, by collecting the operational data for each component and combining these data with theoretical analysis, the sub models were designed and the input parameters, output parameters, and optimization variables of each sub-model were defined. Next, the sub-models were coupled and the control variables of the operational combination, leading to the lowest overall system energy consumption, were obtained using a particle swarm optimization algorithm. Finally, considering a medical building in North China as an example, the application effectiveness of the optimal control strategy of the refrigeration plant was analyzed. The results showed that the energy-savings of the group control system after the optimization of the refrigerator, chilled water pump, cooling water pump, and cooling tower could reach 9.42, 8.04, 5.67, and 14.64%, respectively. This is a remarkable energy-savings benefit. The research described in this study also provides some reference for the design of group control systems in refrigeration plants.

Keywords

• Group control system
• Control strategy optimization
• Particle swarm optimization