Papers by Keyword: Electromagnetic

Abstract: This study introduces a surrogate model-based optimization methodology to explore a wide design space of power module packages for achieving user-defined electromagnetic design objectives, such as minimizing commutation loop stray inductance, gate loop stray inductance and balancing mutual inductance. A half-bridge module with four parallel SiC devices per switch position is analyzed, incorporating 17 design variables across terminals and substrate dimensions. Using Sobol sampling, 4096 design variations were simulated in Ansys Q3D to train the surrogate model, enabling efficient gradient-based single- and multi-objective optimization. Results show that the proposed methodology significantly accelerates exploration in a wide design space and outperforms traditional expert-driven methods by identifying superior electromagnetic performance.

Abstract: In the present work, the composite material Ni_0.16Cu_0.22Zn_0.62Fe₂O₄-BaTiO₃ (NCZF-BTO, in a 10:1) was synthesized with different additive amounts of Li₂O-Al₂O₃-Bi₂O₃-SiO₂ (LABS) glass using a traditional solid-state reaction method and sintered at 900 °C. The synthesized composites were then comparatively investigated; in addition to their phases and density, their magnetic and dielectric properties, which include the saturation magnetization(4πM_s), coercivity (H_c), permeability (μ^'), quality factor (Q), dielectric constant (ε')and dielectric loss (tan δ) were characterized. In contrast to the undoped composites, the performance of the LABS-doped samples were enhanced. The optimal performance was obtained when the LABS glass content reached 1.0wt%. At this level of doping, the bulk density increased from 4.883 g/cm³ to 5.021g/cm³, the saturation magnetization (4πM_s) increased from 3819.5 to 4113.6Gs, the coercivity (H_c) decreased from 111 to 106.5A/m, the permeability (μ^') at 10 MHz increased from 25.8 to 61.1, and the dielectric constant (ε') at 10 MHz increased from 18.9 to 23.4. On further increasing the LABS glass content to1.5 wt%, the performance of the composite generally deteriorated, except for the dielectric constant,which increased to 27.1. In short, the optimal LABS glass doping ratio was determined to be 1.0 wt%.

Abstract: Drying masonry building structures using high-frequency electromagnetic radiation, so-called microwave technology in construction practice is becoming more common. It is an innovative method which can be used to remove excess moisture with significant speed. This article focuses on the description of physical phenomena that occurs during drying and compares the most commonly used processes for drying buildings. This article describes the heating of building materials (basement spaces built from full burnt bricks) using microwave radiation. It assesses the depth of the heating process achieved under different conditions while taking account of various moisture content of irradiated material and varied length of heating.

Abstract: Electromagnetic micro-punching is a novel micro-punching process in which metal foil occur plastic deformation until shear fracture under magnetic impact load. In this paper, electromagnetic micro-punching process was investigated on T2 copper foil. Effects of discharge energy, foil thickness and discharging time on micro punching were discussed. The results show that micro holes were successfully pierced with the discharge energy more than 5.0 kJ on copper foil of 20 μm in thickness. Foil thickness is the main factor in electromagnetic micro-punching with the discharging energy of 7.2 kJ. In addition, increasing discharging time can punch micro hole on thicker foil. The micro holes with diameter of 0.4-1.4 mm were successfully punched on 20 μm copper foil in thickness with discharge energy of 7.2 kJ.

Abstract: Starter motor is an important part of the auto starting system. The basic electromagnetic field distributions of the starter motor considering the armature reaction have been obtained by using Ansoft software, also the magnetic field and flux density of the air-gap. The results of the Gauss Meter validate the accuracy of the finite element model. The main conclusions are helpful to the performance analysis, model calculation and optimization design of the auto starter.

Abstract: In order to study the electromagnetic interference on SAW (surface acoustic wave) wireless temperature measurement system of the corona discharge, the paper analyzes the characteristics of the frequency spectrum of corona discharge, models the corona discharge and studies its radiation characteristics by simulation on Matlab. Based on this, the experimental platforms of corona discharge is set up. The result of the experiment confirms that corona discharge causes electromagnetic interference to the system and the influence decreases as the distance between the sensor and discharge sources increase. Then the sensor should be kept a certain distance from the discharge sources.

Abstract: Most high duty parts used in various fields of productions are forged parts made of steel. The conventional forging process chains include an induction heating systems and hot forming equipment. The large amount of consumed energy and an excess of material (flash) are the main factors motivating necessity to optimize the industrial technologies of metal hot forming. A significant economical effect can be achieved through optimization of heating modes and design parameters of induction heaters on the basis of modern optimal control theory for distributed parameters systems. The aim of the presented research is a problem-oriented simulation of induction heating stage in the forging chain. 2D ANSYS model provides FEM analysis of interrelated electromagnetic, temperature and thermal stress fields during induction heating of a steel cylindrical billet before its hot forming. The model has interface adapted to optimization procedures; it provides more options for variation of the heating system parameters or billet geometry and material properties, and for evaluating the process optimization abilities.

Abstract: Electromagnetic tracking sensor is based on the car with an alternating current through a wire, according to the sensor data collected after the completion of processing of the microprocessor of the car steering rudder adjustment, and by detecting the speed and steering wheels the size of machine-printed on the rudder speed adjustment control. In today's age of advanced technology more and more of our friends that we accelerate the pace of life has accelerated the speed of travel, while the faster and more accidents on the track the car is either the superiority of unmanned vehicles can think and know.

Abstract: Partial discharge (PD) detection using UHF signal is a well known advanced detecting method in GIS and has been actively studied. Numerical simulation using finite difference time domain (FDTD) algorithm is performed to investigate the transmission characteristics of W-M waves excited by partial discharge through straight closed tank of a GIS bus in. The time domain decaying characteristics and frequency domain resonance characteristics is studied in this paper. The simulation results shown that for the closed tank, E-M waves attenuate little during transmission and distribute oscillating in the tank. The distributions are symmetrical at 0 degree and 180 degrees and the energy at the two types of degrees is the same.

Abstract: In order to ensure the control degree of compaction and meet the design requirements in the process of asphalt pavement construction, reduce the core detection for the damage in the late. It using non-nuclear density gauge to test density, and carries on the comparative analysis with the density of core test data or conversion degree of compaction data, then study the variation regularity of after the calibration for field dynamic control compaction with the roller compaction times, Conclusion non-nuclear density gauge control accuracy and error causes in the asphalt layer compaction testing. Experiment results show that non-nuclear density gauge must be proper calibration, which according to different structure layer, gradation type and different materials and core calibration method test values. At the same time suggest appropriate to increase the number of calibration for 10~15 points, which reduce error and test error for choosing, make its accuracy of control within 2%. The conversion relationship between detecting the density and the water method to testing compaction were emphatically studied, this provides a basis for non-nuclear density gauge effective application in the field compaction test grade road asphalt layer.