In recent years, the AC variable-frequency speed-regulation system has become the most promising speed control method, gradually replacing the DC speed control system with its excellent speed control performance, significant power saving effect, and wide applicability in various fields of the world economy [
1]. However, the vibration and noise produced cannot be ignored.
Studies have substantiated that one of the reasons for the vibration and noise of the induction motor powered by a variable frequency is the magnetostrictive effect of the iron core [
2]. In [
3], Fan, W. studied the dynamic model and analysis method of the transmission process of DCDS. In [
4], Maraaba, L.S. presented a novel method for the stator inter-turn fault diagnosis of a wire-started PMSM, which utilizes frequency analysis of the acoustic signals caused by asymmetric faults. In [
5], Chang, Y. H. studied the core vibration of a transformer based on the measurement results of the magnetostriction of silicon steel sheets and gave a mathematical calculation model of magnetostrictive force and electromagnetic force. In [
6], O. A. Mohammed studied the deformation of the motor stator caused by the magnetostrictive effect of the silicon steel sheet. In [
7], K. Delaere studied the magnetostrictive force by measuring the strain of the motor stator, and then calculated the vibration of the motor based on the thermal stress micro-displacement finite element method and analyzed the vibration frequency spectrum. At the same time, the electromagnetic design and manufacturing process of the motor will also affect the vibration and noise of the motor. In [
8], M. Islam studied the vibration and noise of fractional-slot permanent magnet motors with variant pole-slot ratios. In [
9], D. Fodorean calculated the vibration frequency and noise of a DC motor and a permanent magnet motor and concluded that permanent magnet motors are more suitable for a number of low-noise applications than DC motors. In another study [
10], starting from the stiffness of the motor stator, L. Gao analyzed the radial electromagnetic force wave and the harmonic response of the motor stator by an analytical method and the finite element method, and the vibration and noise of a 48-slot, eight-pole motor were simulated. In [
11], based on a special dual-branch three-phase permanent magnet synchronous motor (PMSM), W. Deng presented a method that utilizes a known modified space vector PWM technique that can suppress unpleasant high-frequency vibration noise as well as acoustic noise more effectively than other methods. In [
12], Han, Z. found that the zeroth-spatial-order axial force is dominant for the generation of the vibration and noise in axial-flux motors. In [
13], the performance of the vibration and noise under classical field-oriented control, offline MTPA control, and online MTPA control was investigated.
Researchers have conducted a great deal of research on motor vibration and noise-related issues, but there are few studies on motor silicon steel sheet magnetostriction at different temperatures and frequencies.
Variable-frequency motors usually work under conditions of high temperatures, poor power supply quality, and variable load conditions. Silicon steel sheet manufacturers usually only provide the magnetic characteristic data curve of silicon steel sheets at room temperature and power frequency, which does not reflect the actual operating conditions of the variable-frequency motor. Therefore, it is of great significance to investigate the magnetic properties of the stator core materials of variable-frequency motors resulting in various temperatures and harmonics.
This article considers a frequency conversion motor with a laminated core of a silicon steel sheet and studies its vibration and noise; the electromagnetic force and the magnetostriction of the silicon steel sheet are considered comprehensively. This paper is organized as follows. Firstly, the magnetic properties and magnetostrictive properties of a non-oriented silicon steel sheet under different temperatures and harmonics are described. Secondly, the electromagnetic force wave of the variable-frequency motor is calculated; then, the vibration and noise of the 1140 V/75 kW variable-frequency motor are simulated and analyzed by multi-physics coupling, and the vibration test is verified. This paper provides a relatively novel method for calculating the vibration and noise of variable-frequency motors and provides theoretical support and a reference for the design of low-noise motors.