Multibody dynamics model and seismic response analysis for porcelain-housed arrester

To reduce the computational cost and improve the computational efficiency in optimal design of seismic isolation device for ultra-high voltage (UHV) porcelain-housed surge arresters, this paper proposes a novel modeling method for lower degrees of freedom for arresters. The characteristic of the elasticity at the cementing joint between porcelain housing and metallic flange was firstly investigated quantitatively based on test data. It shows that the flexural rigidity distributed unevenly along the axial direction of the arrester, which provides basis for the discretization of elasticity characteristics and the establishment of the multibody model of the arrester. Then, each porcelain unit was taken as a rigid body, and the flexural behavior of the overall system was simulated by torsional springs at flange cementing joint. A model of multibody system with pin-joints and torsional springs was constructed based on the multibody dynamics theory. The joint coordinate method was adopted to derive the governing equations of motion for the multibody system under seismic excitation. Lastly, a 1 000 kV porcelain arrester was modeled by the proposed method, and static analysis and seismic response history analysis were performed. Comparison between calculated results and test results showed a good agreement. Results show that the numbers of degrees of freedom of the multibody system for an arrester was equal to the numbers of its porcelain units, which is usually less than 6. Due to its simplicity in form, it is easy to construct the model of isolated arresters equipped with seismic isolation device by the proposed method. The method can also be easily extended to the seismic analysis of similar column-type porcelain electrical equipment in substation. © 2022 Harbin Institute of Technology. All rights reserved.