Dynamic response of a capacity-modulated linear compressor to supply voltage disturbances

Abstract

Linear compressors are sensitive to external factors such as the ambient temperature and the supply voltage. This paper presents the dynamic response characteristics of a linear compressor to electric supplied voltage disturbances. A prototype compressor was constructed to realize both the conventional linear compressor and the inherent capacity modulated (ICM) linear compressor. The responses of the ICM linear compressor to the supplied voltage change were evaluated and compared with those of the conventional linear compressor at a condensing temperature range of 35–50 °C and an evaporating temperature of −26 °C. The cooling capacity ratio was varied by 4% for the ICM linear compressor and more than 20% for the conventional linear compressor at a normalized voltage change of 5%. Over a normalized voltage change of 5%, the normalized power factor of the ICM linear compressor varied by 4% to mitigate the performance variation, while that of the conventional linear compressor varied by 5% to aggravate the performance variations. These results show that conventional linear compressors cannot be used in appliances without stroke controllers. However, the ICM linear compressor without stroke controllers maintained its performance stability over a wide range of voltage disturbances.