Comparative Analysis of Three Structures of High-Voltage Frequency Converters for Asynchronous Electric Drive

Development of high-voltage converters of frequency is one of actual problems of the modern adjustable electric drive of an alternating current. Construction of high-voltage frequency converters goes in the following directions. First, on the basis of the developed converters of frequency 0.4 kV and 0.69 kV, added with the output high-voltage transformer. Second, by construction of multilevel frequency converters on the basis of new decisions. The combined way when multilevel frequency converters are created on the basis of the combined connection of the fulfilled three-phase bridge VSI cells. In the report the comparison of three variants of high-voltage frequency converters for 6 kV the asynchronous machine of the pump by power 500 kW and higher is made on the basis of the combined way.