ANALYSIS ON FREQUENT SWITCHING OF AC FILTER IN TIANGUANG HVDC PROJECT

Tianguang ±500kV HVDC Project was put into operation since June, 2001. The frequent switching of its AC filters sometimes happened. Here, the reactive power control and the control logic of converter transformer tap changer were analyzed, and the recorded fault data was analyzed in detail by EMTDC program with actual Tianguang HVDC model Analysis results showed that the incorrect setting of the parameters in the tap changer control for converter transformer and reactive power control caused the frequent switching of AC filters. In addition, the practicable improving measures such as modifying the internal parameters of DC contro system, etc., were given.