Controlling pumping limit of variable turbocompressor - by varying return flow to inlet as function of intake flow and output setting

摘要

The arrangement is intended for controlling the pumping limit of a turbocompressor (2) with output control (7) having a return flow line (11) from the pressure to the intake side of the compressor. It comprises a controller (1) which receives a signal representing the actual flow in the inlet line (4) from a flow meter (3) and a signal representing the rated value derived from a load-dependent quantity. The controller output actuates a value (10) in the return line (11). The load-dependent quantity may be proportional to the speed of a variable-speed compressor and/or to the position of the guide vanes of a variable guide vane compressor.