Energy-efficient fluid medium pumping system

摘要

The inventive pumping system includes at least two parallel-working pumps or compressors, at least one of which is operable as either a pump or a turbine in one or both directions, its drive motor being also capable of operating as a generator so as to feed electrical power back into the electrical network to which it is connected when necessary. At high fluid flows all the pumps or turbines act as pumps to cause the fluid medium to flow in one direction, whereas as low fluid flows the normal-acting pump or compressor operates at a relatively high energy-efficient speed while the excess flowing fluid medium is caused to flow in a return fashion through the outer pumps or turbines such that they act as turbines and thus generate electrical energy for feeding back to the electrical network to which it is connected.