Accelerated Life Test Study on Thyristors of HVDC Converter Valve

As the key component of HVDC converter valve system, thyristors have vital impact on the reliability of the entire HVDC transmission project. In order to effectively obtain the life model of thyristor, this paper uses the existing accelerated life test theory, combined with the operating conditions of the converter valve and the relevant characteristics of the thyristors, to deeply analyse the several stress levels that have the most serious impact on the life of the thyristors. An accelerated life test scheme that can effectively guide the life model of the thyristor, according to the test data collected by this test method, the thyristor junction temperature life model under the short-circuit current stress is established, and compared with the thyristor failure rate in the practical engineering, the results show the feasibility of the test scheme and the correctness of the life model.