| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a refrigeration device capable of achieving both of an efficient operation in a normal time and a surge detecting function of high accuracy in emergency, regardless of a magnitude of a load and presence or absence of a hot gas bypass.SOLUTION: A chiller 10 includes a centrifugal compressor 22, a suction guide vane 43, a discharge diffuser width adjustment mechanism 44, and a chiller controller 20. The suction guide vane and the discharge diffuser width adjustment mechanism control a capacity of the compressor by changing an opening. The chiller controller compares an individual surge curve of the compressor with a heat insulating head to execute a control of a rotating speed of the compressor, a control of the rotating speed of the compressor for preventing surge, a control for emergency stop of the compressor based on surge detection. The surge curve is stored in advance in the chiller controller, and defined by a present rotating speed of the compressor, an opening of a suction capacity control mechanism, and an opening of a discharge capacity control mechanism. The heat insulating head is calculated on the basis of a suction pressure, a discharge pressure and a suction temperature, during operation.</p> |
