Research on routine test of thyristor level with TCU in HVDC converter valve

Converter valve is the key equipment in HVDC project, and its performance has a tremendous influence on the reliability, stability and efficiency of the whole power system. Thyristor level unit is the basic unit of HVDC converter valve, so each thyristor level unit needs to be tested routinely before the operation of the power system, which results in huge workloads and high costs. At present, there is no specific test scheme for thyristor level unit with thyristor control unit (TCU). Therefore, it is particularly important to systematically establish the test methods for thyristor level with TCU in order to improve the security and offer technical support for operation and maintenance of converter valve. In this paper, based on the analysis of the electrical principle of the thyristor level unit and IEC 60700-1-2008, the contents and method of routine test for thyristor level unit with TCU are presented, and subsequently adopted in a practical HVDC project to verify its rationality and validity.