Aiming at the problems of high energy consumption and large internal temperature fluctuations in traditional mechanical refrigeration storage, with the development of phase change cold storage technology, researchers have developed a small portable and energy-saving phase change cold storage. By installing refrigeration units and 100 cold storage pipes in the storage, the refrigeration unit is used to provide cold source for the cold storage pipeline and fresh preservation storage when the power consumption is low, and the heat absorption characteristics of the phase change material in the cold storage pipe during the solid-liquid phase transition are used to keep the cold storage in the cold storage at the peak of power consumption, so as to realize the 24 h cycle cooling. The research results show that when the average temperature of the external environment is 30.9 ℃ and the set temperature is 2 ℃, the maximum value of the internal temperature of the refrigeration unit is 2.57 ℃, the minimum value is 1.55 ℃, and the temperature fluctuation is stable; The maximum internal temperature is 3.45 ℃, and the minimum is 1.98 ℃. The temperature rises slowly at night, the maintenance time is longer than 14h, and the temperature uniformity is good. Compared with the traditional mechanical fresh preservation storage, the fresh preservation storage has low energy consumption, uniform temperature and 368 days investment return period.