Analysis on switching transient EMI in ±500-kV HVDC converter stations

Transient processes are generated by operations of disconnect switches and circuit breakers in the AC side of converter stations. Several trips in different ±500-kV HVDC converter stations in china happened recently. Characteristics of transient Electromagnetic Interference due to switching operations are summarized based on onsite tests in a practical converter station. Measurements are performed to analyze the propagation mechanism of transient processes due to variable switching operations. The EM noises generated by switching operations in secondary systems especially the measuring system are analyzed as well. The high frequency characteristics of DC shunts, which is the most important path for EM noise propagation, is analyzed based on tests and calculation.