Abstract A variable speed photovoltaic direct-current (DC) refrigerator (VSPVDR) system is proposed in this paper. In the VSPVDR system, the photovoltaic (PV) cells are directly connected to the compressor without batteries and inverter, and the DC compressor speed changes with the radiation intensity. In the paper, a dynamic model is presented to simulate the behavior of the VSPVDR, and several prototype experiments are conducted to validate the model. On this basis, the impacts of the compressor speed control strategy, ambient temperature and the radiation intensity have been studied. Compared with the fixed speed mode, the cooling capacity of the variable speed mode increases by 32.76% and the average PV utilization efficiency increases by 45.69%. When ambient temperature increases, the average cooling capacity decreases significantly, but the increase of average power consumption is not obvious, which reveals that the ambient temperature has greater influence on the cooling capacity and has less influence on the power consumption. The radiation intensity has a significant impact on system performance. When the radiation intensity increases, the cooling capacity increases significantly.

中文翻译：

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一种变速光伏直流制冷机的动态仿真与实验研究

摘要 本文提出了一种变速光伏直流（DC）制冷机（VSPVDR）系统。在VSPVDR系统中，光伏（PV）电池直接与压缩机相连，无需电池和逆变器，直流压缩机转速随辐射强度而变化。在本文中，提出了一个动态模型来模拟 VSPVDR 的行为，并进行了几个原型实验来验证该模型。在此基础上，研究了压缩机转速控制策略、环境温度和辐射强度的影响。与定速模式相比，变速模式的制冷量提高了32.76%，光伏平均利用效率提高了45.69%。当环境温度升高时，平均制冷量显着下降，但平均功耗的增加并不明显，说明环境温度对制冷量的影响较大，对功耗的影响较小。辐射强度对系统性能有显着影响。当辐射强度增加时，冷却能力显着增加。