Simulation Study of Vibration Characteristics of UHVDC Converter Valve Saturable Reactor Under Broadband Electric Excitation

As a critical component for ensuring the safe and stable operation of converter valves, the saturable reactor must withstand a significant amount of high-order harmonics generated during thyristor switching, which can result in high-frequency vibrations of the saturable reactor. This paper presents a simplified simulation model for the vibration analysis of a saturable reactor under broadband electrical excitation. First, the magnetization curve and magnetostrictive characteristic curve of the silicon steel sheets used in the saturable reactor are measured. Subsequently, vibration tests are conducted on the saturable reactor to obtain vibration data under various loads. A multiphysics coupling model of the saturable reactor is then established. The measured data curves are combined with finite element software to calculate the vibration of the iron core of the saturable reactor. Finally, the simulated results are compared with experimental measurement data. The results show that the discrepancy in magnetic flux density inside the iron core under various loads is within 3% of the theoretical calculated values, and the difference in vibration acceleration of the iron core compared to experimental measurements is less than 20%. This indicates the rationality of the simplified model of the saturable reactor established in this paper for nonlinear vibration analysis under broadband excitation. The model can provide a basis for further in-depth research.