AIR-CONDITIONING DEVICE, RAILWAY VEHICLE AIR-CONDITIONING DEVICE, AND METHOD FOR CONTROLLING AIR-CONDITIONING DEVICE

摘要

An air-conditioning device includes (i) a compressor, (ii) an outdoor heat exchanger, (iii) an indoor heat exchanger and an electronic expansion valve, (iv) a bypass passage communicatively connecting a middle compression chamber and a low pressure space, the middle compression chamber being a chamber to accommodate a refrigerant undergoing compression by the compressor, the low pressure space being a space to accommodate the refrigerant having a pressure lower than a pressure of the refrigerant in the middle compression chamber, (v) a bypass valve to open or close the bypass passage, and (vi) a controller to execute setting of a degree of opening of the electronic expansion valve based on a degree of superheat of a refrigerant. Based on a change from a closed state of the bypass valve to an open state of the bypass valve, the controller starts restriction processing in which the degree of opening of the electronic expansion valve is corrected to a value that is less, by a given degree θa of opening, than a value set by the degree-of-superheat control.