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Magnetically controlled reactors (MCRs) are widely used as reactive power compensation equipment owing to their favorable properties of smoothly adjusting their inductance value through dc bias. However, the dc bias and the rotational magnetization at corner and T-joint areas make the cores of MCRs saturated, resulting in high magnetostriction and vibration. Thus, the electromagnetic vibration analysis of MCRs must consider the vector hysteretic magnetostriction effect. In this article, a vector hysteretic magnetostriction model of silicon steel is proposed by combining the quadratic domain rotation model with the vector inverse Jiles–Atherton model firstly. Then, based on the measured magnetization and magnetostrictive characteristics curves of silicon steel, the model’s parameters are optimized by velocity controllable particle swarm optimization (VCPSO). Finally, the vector hysteretic magnetostriction model is combined with the finite element method (FEM) to simulate the vector vibration characteristics of MCR under dc bias. The simulation results show that the vector property of electromagnetic vibration and magnetic field at the T-joint area is higher than that at other areas. And the MCR vibration test results are consistent with the simulation results, which verify the accuracy of the proposed model in simulating electromagnetic vibration. [ABSTRACT FROM AUTHOR]

The vibration of permanent magnet synchronous motor (PMSM) cores is related to the rotation speed. This paper presents a generalized magnetoelastic 3-D finite-element model, which can be used to calculate the magnetic field and structural vibration of laminated cores, including magnetostrictive effect. Magnetostriction (MS) is a property of electrical steel and causes the vibration of motor cores, the primary cause being electromagnetic forces. To implement the model, the vibration of a PMSM core was numerically analyzed under excitation with different frequencies. The speed and vibration were measured simultaneously by pulse and accelerometer sensors, and the variation of speed and vibration features was analyzed by Fast Fourier Transformation (FFT) versus Revolutions per minute (RPM). The numerically analyzed results showed that the vibration due to MS is important, and the magnitude of vibration is related to the operating speed. Vibration and speeds of the motor were tested and analyzed. The results showed that there is a vibration peak in the range of 600–2000 r/min (30–100 Hz), which is acceptable in calculation. [ABSTRACT FROM AUTHOR]

The total noise level of transformers is mainly influenced by harmonics in load current. The reasons are the interaction of harmonics with large load current at power frequency and the rising sound radiation efficiency with frequency. It is noted that the dynamic vibration behaviors under load harmonics operation are important to decrease the equipment noise. This paper mainly studies the vibration noise effects of three-phase three-leg transformer with the load of wireless power transfer (WPT) system, which would bring harmonics in the load current. Accelerometer sensors were arranged on the surface of the cores and windings of the transformer. Then, the vibration was measured in different positions of a transformer under the power of WPT system from 0 to 20 kW. The spectral distribution of vibration was obtained through the fast-Fourier transform analysis of the acquisition signals. The experimental results with and without PWT load imply that the harmonics in load-current have great effect on the vibration noise. It is to conclude that the main several harmonics of load current should be eliminated to reduce the vibration noise level. [ABSTRACT FROM AUTHOR]