Dynamic ice storage system has advantages of energy-saving by using electricity price difference of the different period. Food in display cabinet requires small temperature fluctuation to prolong preservation time. Considering the questions of energy consumption and unable to adopt the traditional method of halting and running compressor to control center temperature fluctuation in display cabinet, the paper provides dynamic ice storage system to cool display cabinet. When the wind speed keeps in suitable space, according to environment temperature, humidity and wind change, self-adaptive adjusting cooling water pump flow can maintain the center temperature within a certain range, and reduce center temperature fluctuations in display cabinet by controlling inverter frequency using PLC. Experiments prove that when environment temperature change range is 20°C to 32°C, and relative humidity is 40% to 90%, if not adopting PLC control pump flow, the temperature difference is 2.5°C, on the contrary, temperature difference is 1.3°C.