Study on energy consumption model of multi-unit air conditioning system with digital scroll compressor

The objectives of this study were to: (i) build simulation model for mult-unit air conditioning (AC) system with digital scroll compressor (DSC) and validate its precision by experiments; (ii) build system energy consumption calculation model by simulation. Lumped parameter model of compressor and electronic expansion valve, and district lumped parameter model of condenser and evaporator were employed in simulation program of multi-unit AC system with DSC. The results indicated that errors between simulated value and experimental data of system hourly energy consumption were within 10%. The simulation model showed good precision. Simulation results indicated that system hourly energy consumption differences caused by indoor unit operating number were less than 15%, which can be neglected. Thus, hourly energy consumption (HW), hourly energy efficiency ratio (HEER) and hourly heating performance factor (HHPF) calculation model of multi-unit AC system with DSC were built based on simulation results. Simulation results indicated that the variation of HW with part load ratio (PLR) and outdoor air temperature presented concave surface distribution and the variations of HEER and HHPF with PLR and and outdoor air temperature presented convex surface distribution. The model provides a tool for energy saving optimization and seasonal energy consumption evaluation of multi-unit AC system with DSC.