Oscillation Test for DC Circuit-breaker Completed at 800kV Taizhou Converter Station

HIMALAYAL - SHANGHAI - CHINA



With two independent attenuation oscillation waveforms displayed on the oscilloscope, electric professionals from Jiangsu Province have carried out the oscillation characteristic test for the first DC circuit-breaker with four fractures at ±800kV Taizhou converter station on June 7, 2017. It marks that the Jiangsu Electric learned more of DC circuit-breaker’s structure and electric feature, improved the technologies of hand-over test for UHVDC project and gained precious practical experience for the construction of following UHV projects.   

As one of important devices at the converter station, the DC circuit-breaker can produce oscillation circuit, forming oscillation current. Overlaid with original current, the forced over-zero point generates and further breaks the DC current. The oscillation circuit’s resistance, capacitance and inductance parameters have an important influence on oscillation characteristics. Hence, it is of significance to detect the oscillation characteristics of DC circuit-breaker. Click here for the circuit-breaker tester.

Previously, the DC circuit-breaker with double-fracture structure was used at domestic DC converter stations. To further improve the capability of breaking current, the circuit-breaker with four fractures was firstly applied at Taizhou converter station. Its electric structure is three fractures in series and then paralleled with the fourth fracture.     

Great efforts were made by Jiangsu Electric Company to guarantee successful completion of this test: extensive researches, in-depth simulation and delicate preparation. The testing is essential to ensure safe operating of converter station.