Application and fault risk assessment for AP1000 primary pump frequency converter

Robicon WC III-HA perfect harmony high voltage frequency converter is used in the power system of AP1000 primary pump. The 6 series power units can achieve direct high voltage output. The converter can achieve perfect switch between two controllers: NXG-A and NXG-B. The application of multiple layer of power unit structure, bypass function and the neutral point offset technique ensure perfect harmonious output of the converter. This paper analyzes the possible failure of the converter and carries out risk assessment. Then corresponding response and improvement measures are put forward in order to reduce the failure rate and increase the economic efficiency. So we can better reflect the superiority of AP1000 technology. (authors)