Air conditioning apparatus usable for wide-range source voltage

An air conditioner including:

• a power-variable compressor;
• an inverter for controlling said compressor to vary a driving frequency of said compressor on the basis of the ratio of an output voltage (V) thereof which corresponds to an air conditioning load and a driving frequency (f) of said compressor;
• a controller for supplying a variable-frequency control instruction in accordance with the air conditioning load to said inverter;
• and
• an input voltage detector for detecting a source voltage input to said inverter, wherein said controller includes reference means for beforehand storing V/f value data corresponding to plural voltage sections to which a predetermined range of the input voltage to said inverter is divided at a predetermined voltage interval, and selects data representing the ratio (V/f) of the output voltage (V) corresponding to the detected input voltage and the driving frequency (f) from said reference means to output the variable frequency control instruction to said inverter so that an air conditioning operation is carried out in accordance with the air conditioning load.