The saturable reactor in Siemens converter valve of ±800 kV UHVDC Fulong converter station has complex structure and low reliability

and its water cooling pipeline is easy to leak during operation

which results in the block locking of DC power system for many times. Based on the analysis of typical defects of saturable reactor in Siemens converter valve and combined with the practice of UHVDC transmission project

a new saturable reactor for Siemens converter valve is designed and developed

which has been successfully applied to the reactor modification of converter valve in Fulong converter station. The test results show that because single winding and single cooling pipeline is designed for the new saturable reactor

not only the external electrical performance

cooling water flow characteristics

structure size and weight of the reactor basically keep unchanged

but also the reliability of cooling water circuit of the reactor is significantly improved

and the operating vibration stress and noise level of the reactor are reduced

which can meet the technology needs of UHVDC transmission project. It has very important engineering application value for improving the intrinsic safety of converter valve equipment and ensuring the energy availability of DC power system.