Efficiency Verification Power Circulation Method of a High Power Low Voltage NPC Converter for Wind Turbines

摘要

Development and research for power converters is concentrated on increasing power density, higher modularity, lower costs as well as higher reliability and efficiency. The use of multilevel converters, like Neutral Point Clamped (NPC) Converters, in high power applications in the range of 1.5MW up to 6MW can be favourable because of the filter size reduction and therefore reduction of weight and total volume of the system. This paper evaluates a high accurate practical efficiency verification in a circulation power testrun for a three level NPC converter with an apparent power of approximately 1MVA.