Optimal Planning of Multi-Compressors Refrigeration System for Maximising Efficiency with the Influence of Weather Condition

Abstract

The formulation of optimisation modelling for the multi-compressors refrigeration system is studied to maximise the efficiency of the system. The main challenge to formulate actual representation of the system occurs when some assumptions are oversimplified in the model formulations. The cooling load with the effect of ambient temperatures are usually not predicted in the model formulations and it is assumed to be a constant value. The options to decide which compressor to operate or in a standby mode is usually unavailable. The reason for simplified model assumptions is due to the lack in understanding the optimization problems and limited data availability. The main aim of this proposal is to formulate a mathematical model for the whole process of the vapour compression refrigeration system and to find the maximum coefficient of performance profile. The formulation of the optimization modelling for the system is modelled as Linear Programming Model to establish an accurate representation of the theoretical process integration of each component in the system. The real-time data for energy consumption, cooling load, and the temperature deviation can be obtained from the building management system. Statistical analysis such as time-series and regression methods are applied to find the relation of energy consumption profile with the ambient temperatures. The optimization modelling is modelled in General Algebraic Modelling Software and solved by a CPLEX solver to evaluate the optimum solution. The outcome is the operational planning of the multi-compressors network over the planning time points and the optimal time-varying coefficient of performance profile for the system that is obtained from the optimal solution with the main aim of obtaining highly efficient performance of the system. The total power consumption of multi-compressors refrigeration system by 43 % in comparison to conventional operation. This study will be beneficial to systematically evaluate the potential control strategy for achieving optimal operation of the refrigeration system.