Iron losses in non-oriented steel subjected to matrix and DC-link converter supply : an experimental and analytical study on variable speed drives

摘要

A system approach to variable speed drives consisting of two low voltage induction motors (Y and A connection) fed by matrix and two-level DC-link converters is developed (chapter 7). The ratio of iron to copper winding losses is studied based on the induction motor equivalent circuit and constant V/f converter control. Electrical efficiency increased by up to 10% (partial load and low speed) in Y-connected motors fed by the matrix converter. While similar values of efficiency were observed in A-configured motors, up to 8% higher output power is extracted from the machines under two-level DC-link converter supply.