44 / 2022-03-05 22:51:51

Vibration characteristics of converter transformers under inrush current

inrush current; vibration; transformer

To investigate the vibration performance of converter transformer, vibration on-line monitoring system were installed on 12 unit of ±800kV YY and YD converter transformers. Vibration data under different magnitude of inrush current has been collected. Under the effect of  inrush current, the vibration magnitude of converter transformers increases significantly and decreases exponentially to stable state. The main vibration frequency is mainly the odd times of 50 Hz such as 350 and 450 Hz. It is found that the vibration magnitude of YD converter transformer is higher than that of YY converter transformer on average, and the decay duration of the odd times of 50 Hz vibration component of YD converter transformer is also longer.  Based on our research, assessment suggestions are proposed. Distributions of vibration features of converter transformers under stable no-load operation are obtained. Research results can provide useful references to the assessment of the vibration condition of ±800kV converter transformers.