Research on the control of thermal and humidity field in precooling

The concordance of the electricity and control system focusing on the PLC is researched and the PID control strategy for thermal and humidity field in precooling is analyzed. Two different modes of the thermal and humidity control, frequency conversion cooling and full-frequency cooling, are compared by the experiments. It is shown that more time, stable cooling process and smaller fluctuating magnitude are gained for the frequency conversion cooling. The effect of different distribution equipments for cold air flow in thermal field in the precooling storage is researched. It is concluded that the way of the orifice flow equalization is better than the blast way of the conventional single fan, both fan, and jacket by mean-variance analysis.