Vibration modal analysis and calculation of a new HVDC converter transformer with inductive filtering method

In this paper, the vibration modal characteristics are investigated for a new high-voltage direct current (HVDC) converter transformer with inductive filtering method. A 3-D finite element model of the transformer is established by means of ANSYS and used to extract natural frequencies and vibration modes of the windings and cores of the converter transformer. First, a new converter transformer based on the inductive filtering is proposed, and its physical structures are described in brief. Then, 3-D model of windings of the new converter transformer is established to calculate the vibration mode. Then, the vibration mode of iron core is investigated, and an effective method of installing pre-tighten clamping is proposed to reduce the vibration of iron core. Finally, the vibration mode of whole transformer is investigated and the results show that proposed transformer has a good performance in vibration. Besides, the proposed vibration modal analysis is useful for the design of the new HVDC converter transformer. Based on the vibration analysis results, we can take the corresponding method to reduce the possibility of resonance caused by harmonic currents.