Improving the Reliability of Semiconductor Converters

Abstract

This paper considers the opportunities for improving the reliability of power semiconductor converters by increasing the installed capacity margin and modifying the configuration of power circuit diagrams. As shown by regression analysis, the unit cost of an autonomous voltage inverter with an increase in the installed capacity of the frequency converter rises by about 25%. It is shown that the machine and the semiconductor converter are used most efficiently in six phases, whereas the number of valves in the semiconductor converter is 4m, where m is the number of phases. A further increase in the number of phases does not significantly reduce the phase current, but significantly increases the number of keys in the valve converter. It is shown that an increase in the phase of power circuit layouts allows using the electric machine more fully in terms of capacity and reduce the phase current in semiconductor converters by more than twofold. It is established that the new solutions allow reducing by almost twofold the number of failures in electric drives of more than 500 kW in capacity, while the costs of power electric equipment increase by no more than 25%.