International Journal of Applied Electromagnetics and Mechanics - Volume 62, issue 3

Authors: Guo, Yujing | Jin, Ping | Ding, Yan | Zhao, Kai | Issoufou, Abdoul Zaid

Article Type: Research Article

Abstract: In this paper, one kind of U-shape permanent magnet embedded salient pole wind generator is proposed. The permanent magnet is divided into three sections to form a U-shaped structure and inserted into the salient pole in the generator. The size of the PM near the side frame is small, therefore, there is sufficient PM location modification space in the salient pole. Some flux-barriers are set in the upper core of the salient pole, which can reduce the q -axis inductance, and ultimately increases the generator maximum output power. To evaluate the generator’s overall performance, some other important electromagnetic parameters such …as the air-gap flux density, the output voltage, the cogging torque, the output power, and the demagnetization performance are all calculated and analyzed base on finite element method (FEM). All the above parameters are compared with that of one V-shape permanent magnet embedded salient pole wind generator. The analysis results show that, with the same volume of permanent magnet, the proposed U-shape permanent magnet embedded salient pole wind generator has higher power density than the V-shape permanent magnet embedded salient pole wind generator. Show more

Keywords: Electromagnetic parameter analysis, reluctance power, salient pole, wind generator

DOI: 10.3233/JAE-190026

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 62, no. 3, pp. 595-605, 2020

Authors: Zhao, Jianhui | Yue, Pengfei | Wei, Kebiao

Article Type: Research Article

Abstract: A high-speed solenoid valve (HSV) with high dynamic responses is a key component of the common rail injector, where it provides accurate and flexible control of the injection. In this study, finite element methods were used to investigate the eddy current inside an HSV. The results demonstrated that the appearance and change in the eddy current were related to the driving current, and significantly influenced the HSV dynamics, particularly the opening response. By considering the eddy current effect, the calculations were seen to match the experimental data effectively during the opening response, but did not match them strongly during the …closing response. During the HSV opening process, the eddy current at the surface of the magnetic materials impeded the magnetization; during the closing stage, it prevented the magnetic flux inside the magnetic material from spreading out and delayed demagnetization. An eddy current was proven to always block the magnetic field change and worsen the HSV dynamic response. Slotting on the yoke can significantly reduce the open response time, while hardly influence the close response. It was deemed necessary to optimize the HSV structure to weaken the eddy current effect on the opening and closing response. Show more

Keywords: eddy current effect, dynamic response, high-speed solenoid valve, common rail injection system, diesel engine

DOI: 10.3233/JAE-190047

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 62, no. 3, pp. 607-618, 2020

Authors: Yang, Yiyi | Su, Sanqing | Wang, Wei | Ma, Xiaoping | Hu, Jingyu

Article Type: Research Article

Abstract: Metal magnetic memory (MMM) testing method has been proved to be a valid approach to monitor early damage and predict fatigue life, but there is no systematic description and comparison about the characteristics of MMM signals for welding and non-welding specimens with different materials under tension-compression fatigue. Thus, the fatigue tests for Q345B and Q345qC welding and non-welding specimens were carried out and the MMM testing was done synchronously. Then, based on the normal components of MMM signals, H p (y ), and its variations, ΔH p (y ), the slope of ΔH p (y ) fitting …curves, K C , and the average of ΔH p (y ) signals on the whole testing line, ΔH p (y )ave , were extracted as the characteristic parameters for Q345B and Q345qC non-welding specimens, respectively. Additionally, the gradient of “peak–vale” on H p (y ) signals curves, k , and the average of H p (y ) signals in the scope of welding zone, H p (y )ave , were extracted as the characteristic parameters for Q345B and Q345qC welding specimens, respectively. Some conclusions can be drawn by comparison: the variation laws of H p (y ) signals with cyclic loads are related to the material. The characteristic parameters for welding and non-welding specimens with the same material have a certain similarity. Then, the failure of non-welding steel can be warned early by K C or ΔH p (y )ave when the fatigue life has 20% left, but the damage degree of welding specimen should begin to be valued highly once the k or H p (y )ave is decreasing. Finally, the fatigue life of welding and non-welding specimens with different materials can be evaluated effectively by using corresponding magnetic characteristic parameters. Show more

Keywords: Metal magnetic memory (MMM) testing, fatigue life, magnetic characteristic parameter, Q345B and Q345qC steel, weldments

DOI: 10.3233/JAE-190064

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 62, no. 3, pp. 619-643, 2020