Thermodynamic investigation of the photovoltaic direct-drive direct-expansion embedded microchannel refrigeration system for electronic device cooling

The vapor compression refrigeration system is one of the crucial solutions to cooling electronic devices with high heat flux. This paper proposes a novel photovoltaic direct-drive direct-expansion embedded microchannel refrigeration system for cooling electronic devices with high heat flux. This system combines photovoltaic direct-drive technology, microchannel direct cooling technology and vapor compression refrigeration technology. An experimental bench was set up and tested under different running conditions. The energy and exergy analysis was used to evaluate the system performance and provide optimization and improvement directions for the electronic device cooling method. The results show that the highest system COP is 3.67 with a continuous operation time of 6.1 h when the average solar radiation intensity is 935.5 W/m2 and the cooling capacity is 550 W. At that time, the daily average exergy efficiency of the proposed system is 18.5 %. As the ambient temperature increases from 29.0 °C to 36.1 °C, the power consumption of the compressor grows from 148.2 W to 181.3 W, rising by 22.3 %. The COP decreases by 20.0 % from 3.54 to 2.83 at the cooling capacity of 500 W. The PV cells exhibit the maximum exergy loss, which accounts for 91.18 %. Followed by the compressor, which accounts for 85.64 % of the VCR subsystem at an ambient temperature of 36.1 °C.