An Improved Electromagnetic-Structural Coupling Vibration Model of Wound Core Under SPWM Excitation

The modeling and analysis of transformer core electromagnetic vibration considering hysteresis and magnetostrictive effects are challenging multi-physical problems. For SPWM application scenarios, a new vibration-predicting method of the wound core based on electromagnetic-structural coupling model is presented. Firstly, the magnetostriction neural network model based on time-domain characteristics (MNNM-TD) of core strips is established. Compared with the conventional Jiles-Atherton-Sablik (J-A-S) physical model, MNNM-TD can more accurately describe the features of the magnetostriction under SPWM excitation. Secondly, a variable-parameter J-A model based on the simplified Newton's method (SNVP J-A) is presented to obtain the precise flux density distribution. Then, an improved electromagnetic-structural coupling vibration model is built, which is an anisotropic model that simultaneously considers core saturation, hysteresis, and magnetostriction characteristics. Finally, the proposed wound core vibration model is verified by experiments. Under SPWM excitation, the errors of the main components of the acceleration level spectrum are less than 1.65 dB. This paper realizes the accurate prediction of the wound core vibration under SPWM excitation, which will contribute to the development of vibration suppression technology for the power electronics system.