International Journal of Applied Electromagnetics and Mechanics - Volume 46, issue 3

Authors: Yuan, Qian | Han, Bangcheng | Dong, Baotian

Article Type: Research Article

Abstract: In order to find an algorithm to get a better optimization result of high-speed rotor supported by magnetic bearing in BLDCM, we presented a multiple objective optimization results which included three algorithms' in this paper. They are the local Sequential Quadratic Program (SQP) algorithm, the global Genetic Algorithm (GA) and the combined optimization strategy algorithm which combines GA and SQP. The parametric optimization model of a 100 kW BLDCM supported by magnetic bearings was constituted with …software ANSYS and an effective connection between software ANSYS and iSIGHT was used to execute the whole optimization process. To insure the best performance, mass and strength were chosen as the optimization goals, meanwhile, the static strength, dynamic modal, shape and magnetic force of the rotor subassembly were used as the main constrains. Six main dimensions of the subassembly were optimized. The optimization results indicated that the GA can get a higher optimization precision than the other two algorithms and the SQP was not effective in the optimization of magnetic suspended motor rotor subassembly. The GA's optimization result made the mass decrease 7.62 percent with the safe factor is 3.15. The 100 kW BLDCM supported by magnetic bearings was designed and fabricated; the multiple objective optimization results were verified by the prototype. Show more

Keywords: Magnetic suspension motor, optimization, genetic algorithm, combined optimization strategy, static strength and dynamic modal

DOI: 10.3233/JAE-141963

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 663-673, 2014

Authors: Arehpanahi, Mehdi | Jamal, Naser Saberi

Article Type: Research Article

Abstract: In this paper, a new sampling point refinement for saturation modeling in Surface Current Method (SCM) is proposed. In this method the variable permeability inside the magnetic materials due to the saturation is defined by optimization of sampling point number and their positions. In other words, the sampling points inside the material are refined for any current value and air gap variation. These results depend on magnetic energy of sampling points inside the material and the …value of them is strongly depend on sampling point positions. Simulation results verification have been done with the FEM. Show more

Keywords: Saturation, surface current method, magnetic devices, permeability, boundary and magnetic energy

DOI: 10.3233/JAE-141964

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 675-681, 2014

Authors: Taherdangkoo, Mohammad | Taherdangkoo, Reza

Article Type: Research Article

Abstract: We propose a new method for solving the Loney's solenoid benchmark problem based on Blind, Naked Mole-Rats (BNMR) algorithm. The key idea of the algorithm is using a \beta -distribution that can efficiently achieve the best solution for the position and size of two correcting coils in the famous Loney's solenoid problem. The results show the superiority of the proposed method on other previously methods for electromagnetic optimization.

Keywords: Modified BNMR algorithm, Loney's solenoid problem, β-distribution

DOI: 10.3233/JAE-141965

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 683-692, 2014

Authors: Li, Peng | Jin, Feng

Article Type: Research Article

Abstract: The thickness-shear modes in a circular cylindrical piezoelectric transformer considering the effect of an epoxy-bonded layer are analyzed, and an exact solution is obtained from the equations of the linear theory of piezoelectricity. Systematic parametric studies are subsequently carried out to quantify the effects of the epoxy-bonded layer upon the transformer performance, including its thickness, elastic coefficient and mass density. It is demonstrated that whilst the thickness and elastic coefficient of the layer …affect significantly the resonance frequencies, transforming ratio, power density, admittance and efficiency, and its mass density has negligible influence. On condition that the thickness of the epoxy layer is vanishingly small so that it degenerates into the solution by the classical shear-lag model. Upon comparing with the predictions obtained by employing the traditional shear-lag model, it is found that the interface viscous damping is absolutely due to the elastic coefficient of the epoxy layer, and the present structure model is found to be more accurate especially when the thickness of the epoxy layer can not be neglected. Show more

Keywords: Thickness-shear mode, cylindrical piezoelectric transformer, epoxy-bonded layer, shear-lag model, viscous damping

DOI: 10.3233/JAE-141966

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 693-708, 2014

Authors: Xu, Lizhong | Li, Huaiyong

Article Type: Research Article

Abstract: The Authors propose an electromechanical integrated harmonic piezodrive system. The dynamics behavior of the movable tooth drive has important effects on its operating performance. Here, the dynamic equations of the movable tooth drive for the drive system are presented. Using the equations, the natural frequencies and vibrating modes of the movable tooth drive are investigated. Results show that five vibrating modes occur for the movable tooth drive which include system modes, static crown gear modes, …movable tooth modes, translating rotor modes and translating crown gear modes. Eccentric center, thickness and length of the flexible ring, diameter of the movable tooth and speed ratio have significant effects on the natural frequencies of the movable tooth drive and should be selected properly. Show more

Keywords: Electromechanical integrated, harmonic piezodrive, vibrating modes, natural frequency

DOI: 10.3233/JAE-141967

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 709-726, 2014

Authors: Lin, X.J. | Huang, K.M. | Yang, Y.

Article Type: Research Article

Abstract: For the study of microwave chemistry, it is necessary to develop a reactor with small-size and wide operating frequency band. This paper presents a novel microwave coaxial reactor. Its main part is a coaxial cavity, and the input end is a coaxial port filled with PTFE, and the other end is a short circuit terminal. Two orifices which are designed as cut-off waveguides for microwave are attached to the cavity as passageway of sample solutions, so the …reactor can treat the samples continuously. The distributions of electromagnetic field and temperature of this novel microwave coaxial reactor used for heating edible vegetable oil at 915 MHz and 2450 MHz are simulated with finite-element method multi-fields coupling analysis. It is easy to find out that this novel microwave coaxial reactor could work properly over a wide frequency band. Also, the operating frequency could be chosen over a wide frequency band to get the optimal reaction effect to meet the requirements of experiments. Show more

Keywords: Microwave chemistry, coaxial, numerical simulation, heating

DOI: 10.3233/JAE-141969

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 3, pp. 727-737, 2014