Recently, the entire system test of the world's first DC self-recovery energy dissipation device undertaken by NR was successfully completed and witnessed by experts, which laid a solid foundation for the engineering application of DC controllable self-recovery energy dissipation device. NR undertook the system integration design and complete supply of pole II DC controllable self-recovery energy dissipation device for Baihetan Jiangsu ± 800 kV UHV DC transmission project.
NR technical team has brought into play the advantages of multi-disciplinary integration to successfully overcome the problems of DC energy acquisition of thyristor, rapid closing of vacuum electromagnetic repulsion mechanism, etc., and completed the development of key equipment such as thyristor switch, fast mechanical switch, optical current transformer, DC electronic voltage transformer, and energy dissipation device protection & control system.
Insulation performance and operation characteristics
The complete system involved in the test includes a composite jacket lightning arrester, thyristor switch, fast mechanical switch, bypass switch, voltage equalizing resistance, optical current transformer, electronic voltage transformer and protection & control system.
The test items include the entire system insulation test (DC voltage withstand, lightning and operation impulse) and operation test (energy dissipation device input and exit simulation, partial voltage ratio test, and control switch current transfer). The experimental content completely verify the system’s insulation performance and operation characteristics of the controllable energy dissipation device.
All the test contents were witnessed by experts organized by the State Grid, and all tests passed successfully, marking that the world's first set of DC controllable self-recovery energy dissipation devices has engineering application conditions. The equipment will be applied to the Baihetan Jiangsu ± 800kV UHV DC transmission project, providing strong technical support for the power transmission of the Baihetan Hydropower Station.