scholarly journals Integrated Electromagnetic-Thermal Approach to Simulate a GaN-Based Monolithic Half-Bridge for Automotive DC-DC Converter

2021 ◽  
Vol 11 (18) ◽  
pp. 8302
Author(s):  
Giuseppe Mauromicale ◽  
Alessandro Sitta ◽  
Michele Calabretta ◽  
Salvatore Massimo Oliveri ◽  
Gaetano Sequenzia

New technological and packaging solutions are more and more being employed for power semiconductor switches in an automotive environment, especially the SiC- and GaN-based ones. In this framework, new front-end and back-end solutions have been developed, and many more are in the design stage. New and more integrated power devices are useful to guarantee the performances in electric vehicles, in terms of thermal management, size reduction, and low power losses. In this paper, a GaN-based system in package solution is simulated to assess the structure temperature submitted to a Joule heating power loss. The monolithic package solution involves a half-bridge topology, as well as a driver logic. A novel integrated electromagnetic and thermal method, based on finite element simulations, is proposed in this work. More specifically, dynamic electric power losses of the copper interconnections are computed in the first simulation stage, by an electromagnetic model. In the second stage, the obtained losses’ geometrical map is imported in the finite element thermal simulation, and it is considered as the input. Hence, the temperature distribution of the package’s copper traces is computed. The simulation model verifies the proper design of copper traces. The obtained temperature swing avoids any thermal-related reliability bottleneck.

Author(s):  
Jingwen Chen ◽  
Hongshe Dang

Background: Traditional thyristor-based three-phase soft starters of induction motor often suffer from high starting current and heavy harmonics. Moreover, both the trigger pulse generation and driving circuit design are usually complicated. Methods: To address these issues, we propose a novel soft starter structure using fully controlled IGBTs in this paper. Compared to approaches of traditional design, this structure only uses twophase as the input, and each phase is controlled by a power module that is composed of one IGBT and four diodes. Results: Consequently, both driving circuit and control design are greatly simplified due to the requirement of fewer controlled power semiconductor switches, which leads to the reduction of the total cost. Conclusion: Both Matlab/Simulink simulation results and experimental results on a prototype demonstrate that the proposed soft starter can achieve better performances than traditional thyristorbased soft starters for Starting Current (RMS) and harmonics.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1421
Author(s):  
Michał Szulborski ◽  
Sebastian Łapczyński ◽  
Łukasz Kolimas ◽  
Łukasz Kozarek ◽  
Desire Dauphin Rasolomampionona ◽  
...  

In this paper, a detailed three-dimensional, transient, finite element method of fuse link NH000 gG 100 A is proposed. The thermal properties during the operation of the fuses under nominal (100 A) and custom conditions (110 and 120 A) are the main focus of the analyses that were conducted. The work concerns both the outside elements of the fuse link (ceramic body) and the elements inside (current circuit). Both the distribution of the electric current and its impact on the temperature of the construction parts of the fuses during their operating mode have been described. Temperature distribution, power losses and energy dissipation were measured using a numerical model. In order to verify and validate the model, two independent teams of scientists executed experimental research, during which the temperature was measured on different parts of the device involving the rated current. Finally, the two sets of results were put together and compared with those obtained from the simulation tests. A possible significant correlation between the results of the empirical tests and the simulation work was highlighted.


Author(s):  
Ming Zhang ◽  
Yanyao Jiang ◽  
Chu-Hwa Lee

A three-dimensional finite element (FE) model with the consideration of the helix angle of the threads was developed to simulate the second stage self-loosening of a bolted joint. The second stage self-loosening refers to the graduate reduction in clamping force due to the back-off of the nut. The simulations were conducted for two plates jointed by a bolt and a nut and the joint was subjected to transverse or shear loading. An M12×1.75 bolt was used. The application of the preload was simulated by using an orthogonal temperature expansion method. FE simulations were conducted for several loading conditions with different preloads and relative displacements between the two clamped plates. It was found that due to the application of the cyclic transverse load, micro-slip occurred between the contacting surfaces of the engaged threads of the bolt and the nut. In addition, a cyclic bending moment was introduced on the bolted joint. The cyclic bending moment resulted in an oscillation of the contact pressure on the contacting surfaces of the engaged threads. The micro-slip between the engaged threads and the variation of the contact pressure were identified to be the major mechanisms responsible for the self-loosening of a bolted joint. Simplified finite element models were developed that confirmed the mechanisms discovered. The major self-loosening behavior of a bolted joint can be properly reproduced with the FE model developed. The results obtained agree quantitatively with the experimental observations.


2009 ◽  
Vol 419-420 ◽  
pp. 89-92
Author(s):  
Zhuo Yi Yang ◽  
Yong Jie Pang ◽  
Zai Bai Qin

Cylinder shell stiffened by rings is used commonly in submersibles, and structure strength should be verified in the initial design stage considering the thickness of the shell, the number of rings, the shape of ring section and so on. Based on the statistical techniques, a strategy for optimization design of pressure hull is proposed in this paper. Its central idea is that: firstly the design variables are chosen by referring criterion for structure strength, then the samples for analysis are created in the design space; secondly finite element models corresponding to the samples are built and analyzed; thirdly the approximations of these analysis are constructed using these samples and responses obtained by finite element model; finally optimization design result is obtained using response surface model. The result shows that this method that can improve the efficiency and achieve optimal intention has valuable reference information for engineering application.


2021 ◽  
Author(s):  
Krzysztof Fulawka ◽  
Witold Pytel ◽  
Piotr Mertuszka ◽  
Marcin Szumny

<p>Underground laboratories provide a unique environment for various industries and are a suitable place for developing new technologies for mining, geophysical surveys, radiation detection, as well as many other studies and measurements. Unfortunately, any operation in underground excavations is associated with exposure to many hazards not necessarily encountered in surface laboratories. One of the most dangerous events observed in underground conditions is the dynamic manifestation of rock mass pressure in form of rockburst, roof falls and mining tremors. Therefore, proper evaluation of geomechanical risk is a key element ensuring the safety of work in underground conditions. Finite Element Method-based numerical analysis is one of the tools which allow conducting a detailed geomechanical hazard assessment already at the object design stage. The results of such calculations may be the basis for the implementation of preventive measures before running up the underground facility.</p><p>Within this paper, the three-dimensional FEM-based numerical analysis of large-scale underground laboratory located in deep Polish copper mine was presented. The calculations were made with GTS NX software, which allowed determining the changes in the safety factor in surrounding of the analyzed area. Finally, the possibility of underground laboratory establishment, with respect to predicted stress and strain conditions, were determined.</p>


Author(s):  
Shiyong Yang ◽  
Kikuo Nezu

Abstract An inverse finite element (FE) algorithm is proposed for sheet forming process simulation. With the inverse finite element analysis (FEA) program developed, a new method for concurrent engineering (CE) design for sheet metal forming product and process is proposed. After the product geometry is defined by using parametric patches, the input models for process simulation can be created without the necessity to define the initial blank and the geometry of tools, thus simplifying the design process and facilitating the designer to look into the formability and quality of the product being designed at preliminary design stage. With resort to a commercially available software, P3/PATRAN, arbitrarily three-dimensional product can be designed for manufacturability for sheet forming process by following the procedures given.


Author(s):  
Pauline Bouin ◽  
Antoine Fissolo ◽  
Ce´dric Gourdin

This paper covers work carried out by the French Atomic Energy Commission (CEA) to investigate on mechanisms leading to cracking of piping as a result of thermal loading existing in flow mixing zones. The main purpose of this work is to analyse, with a new experiment and its numerical interpretation, and to understand the mechanism of propagation of cracks in such components. To address this issue, a new specimen has been developed on the basis of the Fat3D experiment. This thermal fatigue test consists in heating a 304L steel pre-cracked tube while cyclically injecting ambient water onto its inner surface. The tube is regularly removed from the furnace for a crack characterisation. Finally, the crack growth is evaluated from the crack length differences between two stops. In parallel, a finite element analysis is developed using the finite element Cast3M code. A pipe with a semi-elliptical crack on its inner surface is modelled. A cyclic thermal loading is imposed on the tube. This loading is in agreement with experimental data. The crack propagates through the thickness. A prediction of the velocity of the crack is finally assessed using a Paris’ law type criteria. Finally, this combined experimental and numerical work on 304L austenitic stainless steel pipes will enable to improve existing methods to accurately predict the crack growth under cyclic thermal loadings in austenitic stainless steel pipe at the design stage.


2021 ◽  
Vol 309 ◽  
pp. 01214
Author(s):  
M.V.N Mohan ◽  
Ramesh Bhagat Atul ◽  
Vijay Kumar Dwivedi

Carbon/Carbon composites finds its applications in several high temperature applications in the field of Space, Aviation etc. Designing of components or sub systems with carbon/carbon composites is a challenging task. It requires prediction of elastic properties with a very high accuracy. The prediction can be normally done by analytical, numerical or experimental methods. At the design stage the designers resort to numerical predictions as the experimental methods are not feasible during design stage. Analytical methods are complex and difficult to implement. The designers use numerical methods for prediction of elastic properties using Finite Element Modeling (FEM). The spatial distribution of fibers in matrix has an effect on results of prediction of elastic constants. The generation of random spatial distribution of fibers in representative volume element (RVE) challenging. The present work is aimed at study of effect of spatial distribution of fiber in numerical prediction of elastic properties of unidirectional carbon/carbon composites. MATLAB algorithm is used to generate the spatial distribution of fibers in unidirectional carbon/carbon composites. The RVE elements with various random fiber distributions are modeled using numerical Finite element Model using ABAQUS with EasyPBC plugin. The predicted elastic properties have shown significant variation to uniformly distributed fibers.


Author(s):  
Adriano Castelo ◽  
David White ◽  
Yinghui Tian

In 2000 the first case of pipeline walking (PW) was properly documented when this phenomenon seriously impacted a North Sea high pressure and high temperature (HP/HT) pipeline (Tornes et al. 2000). By then, the main drivers of this problem were accordingly identified for the case studied. On the other hand, to study other aspects related not only to PW, the industry joined forces in the SAFEBUCK Joint Industry Project (JIP) with academic partners. As a result, other drivers, which lead a pipeline to walk, have been identified (Bruton et al. 2010). Nowadays, during the design stage of pipelines, estimates are calculated for pipeline walking. These estimates often use a Rigid-Plastic (RP) soil idealization and the Coulomb friction principle (Carr et al. 2006). Unfortunately, this model does not reflect the real pipe-soil interaction behavior, and in practice time consuming finite element computations are often performed using an Elastic-Perfectly-Plastic (EPP) soil model. In reality, some observed axial pipe-soil responses are extremely non-linear and present a brittle peak strength before a strain softening response (White et al. 2011). This inaccuracy of the soil representation normally overestimates the Walking Rate (WR) (a rigid plastic soil model leads to greater walking). A magnified WR invariably leads to false interpretations besides being unrealistic. Finally, a distorted WR might also demand mitigating measures that could be avoided if the soil had been adequately treated. Unnecessary mitigation has a very strong and negative effect on the project as whole. It will require more financial and time investments for the entire development of the project — from design to construction activities. Therefore, having more realistic and pertinent estimates becomes valuable not only because of budgetary issues but also because of time frame limits. The present paper will show the results of a set of Finite Element Analyses (FEA) performed for a case-study pipeline. The analyses — carried out on ABAQUS software — used a specific subroutine code prepared to appropriately mimic Non-Linear Brittle Peak with Strain Softening (NLBPSS) axial pipe-soil interaction behavior. The specific subroutine code was represented in the Finite Element Models (FEMs) by a series of User Elements (UELs) attached to the pipe elements. The NLBPSS case is a late and exclusive contribution from the present work to the family of available pipeline walking solutions for different forms of axial pipe-soil interaction model. The parametric case-study results are benchmarked against theoretical calculations of pipeline walking showing that the case study results deliver a reasonable accuracy level and are reliable. The results are then distilled into a simplified method in which the WR for NLBPSS soil can be estimated by adjusting a solution derived for RP and EPP soil. The key outcome is a genuine method to correct the WR resultant from a RP soil approach to allow for peak and softening behaviour. It provides a design tool that extends beyond the previously-available solutions and allows more rapid and efficient predictions of pipeline walking to be made. This contribution clarifies, for the downslope walking case, what is the most appropriate basis to incorporate or idealize the soil characteristics within the axial Pipe-Soil Interaction (PSI) response when performing PW assessments.


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