Abstract：Characterizing the connection parameters of the bolted joint between the electrical steel sheets is the key to the dynamic analysis of the core. Aiming at the problem of large error in parameter identification of transformer core dynamic model, a gradient connection layer model considering the pressure distribution of the bolted joint was proposed. The pressure distribution of the bolted joint was obtained through theoretical calculation, and the relationship between the elastic parameters of the gradient connection layer and the contact pressure of the bolted joint was derived. Based on the obtained equivalent material parameters of laminated electrical steel beams, a gradient connection layer model was established to simulate the bolted joint between two identical laminated electrical steel beams connected by bolts. The elastic parameters of the gradient connection layer were updated by comparing the experimental modals with calculated modals. The calculated modals’ first eight order vibration shapes of the laminated electrical steel beams connected by bolt are consistent with the experimental modals’ after updating, and the relative errors of the corresponding natural frequency are within 1%, which proves the accuracy of the gradient connection layer model. Applying the updated gradient connection layer model in transformer core can improve the modeling accuracy.
关天赐，王小鹏，奚延辉. 应用梯度连接层的层合电工钢梁螺栓结合部简化模型研究[J]. 振动与冲击, 2022, 41(5): 67-74.
GUAN Tianci, WANG Xiaopeng, XI Yanhui. Simplified model of bolted joint of laminated electrical steel beam using gradient connection layer. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(5): 67-74.
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