AFT9339 series Static Frequency Converter  is a three-phase in and three-phase out high frequency converter  with medium power capacity. It adopts special technology and high-frequency electric switch change technology.  Equipped with three-level inverter topology, it results in high efficiency. Adopting unique power unit redundancy design technology, decrease the abnormity risk of system after single-point failure, greatly increase the system reliability. It is the substitute of the unit frequency conversion power supply, also it is applied to laboratory and product line as debugging power supply.