Abstract: Pressure difference defrosting control method has been used in existing cold storage, but its pressure difference threshold is difficult to define, which leads to poor defrosting effect, resulting in obvious waste of energy or poor cooling performance. To solve the problem, in this paper, a realtime operation parameter acquisition and control system of the cold store is built based on MCGS. Based on this, the temperature difference between evaporator inlet and outlet is determined as the exit judgment parameter of defrosting operation. In this paper, the defrosting times, refrigerating effect, temperature fluctuation and energy consumption of the cold store under various static pressure differences （the difference between the evaporator inlet air pressure and the static air pressure at the cold store） are studied by experiment. The results show that the higher the static pressure difference, the more defrosting times. When the static pressure difference is 16 Pa, 14 Pa, 12 Pa, 10 Pa, the unit refrigeration effect is stable, and the reservoir temperature fluctuation is not obvious. When the static pressure difference is 8 Pa, the unit refrigeration effect decreases, resulting in prolonged cooling time and serious reservoir temperature fluctuation. When the static pressure difference is 10 Pa, the energy consumption is lowest, and when the static pressure difference is 8 Pa, the energy consumption is highest.

Key words: cold store, pressure difference defrosting control method, static pressure difference, energy consumption

摘要： 压差除霜控制法在现有冷库已有一定应用，由于压差阈值难以界定，除霜效果不佳，造成明显的能耗浪费或者机组制冷性能下降。针对该问题，基于MCGS搭建一套冷库实时运行参数采集及控制系统；在此基础上，将蒸发器进出口温度差值定为除霜操作退出判断参数，通过试验法研究冷库在不同静压差值（蒸发器进风口气压与冷库内空气静止处气压的差值）介入除霜时的除霜次数、机组制冷效果、冷库温度波动和能耗变化规律。结果表明：相同时间内，介入除霜的静压差值越高，除霜次数越多；静压差值为16 Pa、14 Pa、12 Pa、10 Pa介入除霜时，机组制冷效果稳定，冷库温度波动并不明显，静压差值为8 Pa介入除霜时，机组制冷效果下降导致制冷时间延长，冷库温度波动严重；静压差值为10 Pa介入除霜时，能耗最低，静压差值为8 Pa介入除霜时，能耗最高。

关键词: 冷库, 压差除霜控制法, 静压差值, 能耗