Turbomechanisms are the machines of mass application. Suffice it to say that about 25% of all electric power generated in the country is spent for the electric drive of pumps, fans and compressors. Technical perfection and profitability of electric drive turbomechanisms substantially define the rationality of electric power use in national economy. When dealing with profitability of the electric drive not only its minimal cost and high power parameters but also such quality of the electric drive as adjustability should be kept in mind. High profitability of the electric drive allows turbomechanisms to do the necessary according to technological conditions work with the minimum consumption of energy. One of the most important problems both at designing and at variable speed electric drive operation for pump units is maintenance of efficiency in productivity regulation. By this means, for example, in pump installations of water supply systems and water removal about 15% and more consumed electric power is lost only because of uneconomical ways of productivity regulation. Effective solution of the specified problem is application of variable speed drive with induction motors. The majority of pump units in housing and communal services is equipped by one high-speed three-phase induction motor with a squirrel-cage rotor. In this case it is the most appropriate way to adjust speed by means of frequency converter.
展开▼
