Measurements of electromagnetic interference in an operating ±800 kV DC converter station

Electromagnetic interference is one of the critical problems to the safety and stability of HVDC and UHVDC systems. When the±800 kV converter station changes the operating states, the breaker and switch operations will cause transient with sharp voltage and current change in the primary circuit and interference into the secondary system. The characteristics of switching EMI under different system states are analyzed based on onsite tests in an operating ±800 kV converter station in South China. The relations between the secondary cable parameters (sheath grounding conditions, length and location) and the induced EMI are tested and investigated in the converter station.