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This paper describes how to design the output filter of a pulsewidth-modulation inverter used in an uninterruptible power supply. Several constraints apply to this design: physical limitations of all material and components, output waveform quality, losses, cost, etc. All models used in the design process are described: semiconductor, inductor and capacitor losses, cost, total harmonic distortion, short-circuit behavior, etc. Input parameters are control law, switching frequency, inductor design parameters (number of turns and magnetic circuit), and capacitor values. Based on these design models, optimization is carried out, and cost-losses tradeoff curves are deduced. Two power levels (30 and 300 kVA) are taken as design example, with the same models, in order to show the robustness of the method. Index Terms--Circuit modeling, circuit optimization, design automation, power electronics, uninterruptible power systems.

Double-sided power modules are particularly attractive due to their high thermal performance. Thanks to the stacking of two direct bond coppers, very low stray inductances may be expected, particularly because of the proximity of the two rear metalizations. On the other hand, capacitive effects may be increased. In this paper, the complete electromagnetic behavior of double-sided power modules is studied, regarding both internal coupling and unwanted electromagnetic compatibility emissions. Some layout and active solutions are proposed to reduce common-mode emissions. Index Terms--Electromagnetic compatibility, hybrid integrated circuit interconnections, hybrid integrated circuit packaging, power electronics, printed circuit layout.

The choice of a set of capacitors for a dc link may be very different depending on the system requirements and user constraints. This paper shows how to achieve the best choice of a hybrid association of electrolytic capacitor and higher frequency technology (polyester for instance). Maximum allowed rms current in the electrolytic capacitor is obviously taken into account. The input filter of a buck converter is chosen as example. Various constraints are considered: voltage ripple, differential-mode electromagnetic-interference level, losses, weight, volume, surface, etc. Objective function for optimization is defined by the user and may be any of the previous parameters. The optimized result consists in the number and the values of components for both capacitor technologies. Index Terms--Circuit optimization, dc-dc power conversion, electrolytic capacitors, electromagnetic compatibility, power electronics.

Due to high-current commutation speed, it has become necessary to minimize stray inductances to reduce over-voltage. This is a great challenge for the power-converter designer. Integration of converters into ever smaller packages decreases stray inductance considerably but, at the same time, increases other phenomena (thermal issues and electromagnetic-compatibility disturbances) capable of decreasing reliability and efficiency of the system. This paper presents a generic equivalent cabling model and examines the impact of parasitic inductance on current-distribution imbalance. This paper could, therefore, be used in thermal analysis in order to better understand the influence of packaging. Index Terms--Layout optimization, paralleling devices, partial element equivalent circuit (PEEC) method, power drive interaction, power electronics, power modules.

The layout of power multichip modules is one of the key points of a module design, especially for high power densities, where couplings are enlarged. This paper focuses on dynamic current imbalance between paralleled chips. It can be principally attributed to gate circuit dissymmetry, which modifies inductances and coupling, especially with the power circuit. This paper describes the analysis of an existing power module. An optimization process based on a modification of the gate circuit geometry allows balancing current during switching phases. This approach will be validated with experimental measurements and applied on an existing module. Index Terms--Direct bonding copper (DBC) tracks, power multichip modules, printed circuit board (PCB).

Design of integrated power systems requires prototype-less approaches. Accurate simulations are necessary for analysis and verification purposes. Simulation relies on component models and associated parameters. The paper focuses on a step-by-step extraction procedure for the design parameters of a one-dimensional finite-element-method (FEM) model of the PiN diode. The design parameters are also available for diverse physics-based analytical models. The PiN diode remains a complex device to model particularly during switching transients. The paper demonstrates that a simple FEM model may be considered unknowingly of the device exact technology. Heterogeneous simulation is illustrated. The state-of-art of parameter extraction methods is briefly recalled. The proposed procedure is detailed. The diode model and extracted parameters are systematically validated from electro-thermal point-of-view. Validity domains are discussed. Index Terms--Finite-element-method (FEM), PiN diode.

This article aims determining the minimum decoupling capacitor Cdec for a railway traction inverter. It is defined when any increase of its value does not decrease the overvoltage at turn off anymore. A simple generic model is deduced from a full understanding of the switching cell behavior, including the effect of all stray inductances and all interactions within the switching cell. This model is used in an optimization process in order to obtain directly the minimal value of Cdec. The methodology is validated in comparison with time simulation, as well as using experimental results. It has been used to analyze the impact of the switching cell parameters on the minimum value of Cdec: switching speed; stray inductances; and additional resistance have been considered. [ABSTRACT FROM AUTHOR]

This paper shows a comparison between Vector fitting and rational Krylov fitting techniques for the determination of rational models concerning the fitting accuracy, the computational performances and the model order. Primarily, the mathematics behind the second technique are presented. It should be noted that rational Krylov fitting have never been used in transmission line modeling. A new procedure is proposed to use rational Krylov fitting instead of vector fitting in the universal line model (ULM). Furthermore, it is demonstrated that this procedure has several advantages over the traditional one. Two illustrative examples involving a transmission system are presented for validation of the new procedure. [ABSTRACT FROM AUTHOR]

A new boundary element method (BEM) formulation has been developed for the computation of 3D eddy currents in both magnetic and conductive regions. The modified magnetic vector potential A∗ in the active regions and the reduced magnetic scalar potential φ in the air are used as unknown variables. The formulation is limited to low‐frequency magneto‐harmonic problems associated to linear, homogeneous, isotropic, and simply‐connected regions. In such a configuration, it leads to accurate results with a reduced number of degrees of freedom located on a surface mesh delimiting the air/material interface. [ABSTRACT FROM AUTHOR]