Regulating the characteristics of a variable-speed centrifugal refrigeration compressor

The performance is examined for methods of regulating the characteristics of a two-stage refrigeration compressor for a water-cooling machine: change in flow direction at the inlet to the rotor by means of an input regulator (IR); change in the rotor speed; and combined regulation (with change in the angle of rotation of the regulator blades). Two modes of operation are considered: the constant or variable throughput subject to change in the temperature of the water at the inlet to the condenser. It is found that combined regulation has good performance.