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This paper introduces a thermal design method for 3D integration, using stacked thermal chips consisting of 100 polysilicon heaters in a 30 mm by 30 mm area on each chip to verify thermal models. For each heater, two levels of thermal load can be selected. Thermal effects from hot-spots in stacked chips were measured and verified in simulation results. Through this investigation, thermal models with...
Thermal cycle testing is required sometimes as a type test for stator bar production for hydro generators. Based on the outcome of the test, a production is qualified by the owner or operator of the generating station. Because of this, it is important that the measurements performed during this test are as precise and non-intrusive as possible. During a previous investigation on thermal cycle testing,...
We have performed the solution of the non-stationary thermal conductivity problem for a single-core copper cable with PVC-plastic insulation. The necessity of solving this problem is due to the strong dependence of the insulation properties on temperature. The solution is made numerically by the finite element method. The problem is solved in a two-dimensional formulation. Flat triangular finite elements...
Advanced power module packaging technology is currently being heavily investigated to take full advantage of Wide Band Gap (WBG) power semiconductor devices. As one of most widely applied power module technologies, intelligent power modules, typically for automotive industries, work well to achieve higher operating frequencies with lower losses by integrating gate driver circuits with power semiconductor...
The next generation of switches for power electronics is based upon Wide Band Gap semiconductors (WBG), e.g. GaN or SiC. These materials are supporting the possibility of higher switching currents and high frequency applications. Wide band gap semiconductors enable high voltage and high temperature applications. Power electronics need an optimized low inductive commutation cell for reducing the switching...
Within the scope of this work, we study the impact of embedded mini heat pipes on the overall thermal performance of PCBs. In a first step, the heat transfer of miniaturized heat pipes is quantified by measurements. The effective thermal conductivity and the maximum admissible heat flow are determined in dependence of the environment temperature and gravitational field orientations. In a second step,...
Molybdenum-copper-composites are interesting materials in the field of thermal management of gallium nitride based electronic devices. Depending on the application and packaging requirements, the coefficient of thermal expansion and thermal conductivity can be tailored for these composites by varying structure and composition. In this work, the interface between molybdenum and copper is studied. Transmission...
A novel nanocopper-based packaging material was developed for robust, void-free thermal interfaces between LEDs and heat sinks/spreaders. It is applicable to other high power components and devices allowing sub-10 micron thermal interfaces to enable high heat transfer rates. Other applications are in TSV & wafer level packaging, embedded chip packaging, direct print of Si and Glass interposers,...
As transformer accidents occur frequently, one of the main reason for such accidents has been confirmed after the disassemble researches with the deterioration of oil-paper insulation caused by the existence of corrosive sulfide. Taking this situation into consideration, a volume of researches have been undertaken in this paper to understand the effect of different dibenzyl disulfide (DBDS) concentration...
Innovative application of carbon composite layers into multilayer printed circuit boards affords CTE matching to semiconductor materials, PCB warpage control, weight reduction, heat transfer, and reduced component operating temperatures for improved performance and enhanced reliability. Manufacturing processes have been developed and matured for thin sheets of CTE-matched composites, attributes and...
A design of a G-band TE01 mode converter is presented in this work. It consists of a TE01 mode launcher followed by a tapered waveguide section. Full-wave simulated reflection coefficient of stainless steel converter is better than −15 dB and transmission coefficient is better than −1.5 dB in a frequency range from 173 GHz to 193 GHz. The design is useful in applications employing highly overmoded...
W/Cu composites have received much attention for applications as in electronic packaging and heat sink materials. There exists difficulties in fabricating W/Cu composites due to the mutual insolubility of tungsten and copper. In this article, high density 1 wt. %Ag-W/Cu composites are prepared by sintering the mixed powders of copper-coated tungsten powders and silver-coated copper powders under different...
Latest Computational Fluid Dynamic tools allow modelling more finely the conjugate thermo-fluidic behaviour of a single electronic component mounted on a Printed Wiring Board. A realistic three-dimensional representation of a large set of electric copper traces of its composite structure is henceforth achievable. So it is possible to confront the predictions of the fully detailed numerical model of...
This paper discusses the manufacturing aspects for Insulated-Metal-Substrates (IMSs) with respect to high thermal conductive prepregs used and the Cu/prepreg/Cu stacks selected for each power application in the project. The IMS heat spreaders serve as high-current PCBs and heat dissipation routes for double side cooling of the Embedded power cores. The interconnection of the embedded power cores to...
The copper vapor resulting from electrode surfaces in arc devices, such as circuit breakers, may modify the characteristics of arc plasmas. The corresponding properties of plasmas contaminated by the metallic vapor are therefore needed to be determined before setting up physical models. In this paper, the equilibrium compositions, thermodynamic properties, transport coefficients, and combined diffusion...
A new three dimensional package based on Printed Circuit Board (PCB) embedded die technology is presented in this paper. The package takes advantage of the Power Chip On Chip (PCOC) concept, where commutation cell is housed within the bus bar, allowing a very low inductance design for the package of up to 0.25 nH. Two key design challenges with the package relate to the layout and the thermal management...
When an electric motor is running for a long time, its winding temperature increases due to ohmic heating in the copper wire. Because the winding is covered with insulating paint, heat dissipation is difficult and this can reduce the service life of electric motor. In view of the difficult problem of heat dissipation with insulation structure, this paper developed a new type of high thermal insulation...
This paper deals with the general problem of the estimation of physical parameters in the presence of nuisance parameters for which an explicit characterisation of the uncertainty is available. Within a Bayesian context, the maximum a posteriori estimation is used. The asymptotic confidence ellipsoid is then determined. The projection of the latter onto the parameter axes is used to obtain the confidence...
This chapter discusses the use, physical and chemical properties of copper. Copper is an essential co‐factor in several enzyme systems. It also has important industrial properties, including efficient thermal and electrical conductivity and resistance to corrosion. Environmental copper has anthropogenic and natural origins (sea spray, hazardous waste dumps, wastewater processing, and industry). Increases...
This paper considers thermal modeling of a 2 MW permanent magnet machine designed and manufactured for marine applications. The main focus is placed on the winding made of the Litz wire, and a practical approach to model heat transfer is presented. The proposed thermal modeling method, named segment-layer, is compared to traditional thermal models used mainly for standard winding configurations. In...
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