Reverse rotation preventing structure of centrifugal compressor

A reverse rotation preventing structure of a centrifugal compressor, wherein the centrifugal compressor compresses a low-temperature and low-pressure refrigerant sucked through a suction port into a high-temperature and high-pressure refrigerant and discharges the high-temperature and high-pressure refrigerant through a discharge port, the reverse rotation preventing structure comprising:

• a suction pipe extended from the suction port;
• a discharge pipe extended from the discharge port;
• a fluid passage pipe connected between the suction pipe and the discharge pipe, wherein an opening and closing of the fluid passage pipe is controlled by a predetermined bypass valve mounted thereon;
• and
• a power-down detecting means for detecting a power-down of the centrifugal compressor and generating a power-down detecting signal so that the high-temperature refrigerant is allowed to flow to the suction pipe through the fluid passage pipe.