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In this paper, heat extractors are embedded into the magnetic materials of the integrated power electronics passive modules. The optimum volume of heat-extracting material may slightly reduce the amount of electromagnetic energy that is processed, but more efficient heat removal yields higher allowable levels of both electromagnetic stress and losses per unit volume in the remaining material. Without influencing the electromagnetic performance, heat extractors provide the potential to improve the power density of passive modules. This paper introduces the mechanism of heat extractors into passive power electronics modules. Theoretical thermal models and simulation are used to investigate factors influencing the module performance and the improvement on power density. Prototypes are built for experimental investigation. The experimental results show great improvement of power density by the application of heat extraction technology. High power density, more than 1 kW/[in.sup.3] (70 W/[cm.sup.3] ), is achieved on the prototype. Index Terms--Embedded heat extractor, passive integrated power electronics module, power density.

In this paper, effects of parasitic parameters on the electromagnetic interference (EMI) filter performance are first discussed. The parasitic cancellation techniques for both self-and mutual parasitics are then reviewed and their constraints are identified. The possibilities of integrating parasitic cancellation techniques into one EMI filter are analyzed. It is found that three parasitic cancellation techniques can be integrated into one EMI filter to improve both differential-mode and common-mode filter performances without any conflicts and compromises. Experiments are finally carried out to verify the integration of these three cancellation techniques. Index Terms--Electromagnetic interference (EMI) filter, equivalent parallel capacitance (EPC), equivalent series inductance (ESL), mutual coupling, parasitic cancellation.

This paper presents a double-sided liquid cooling scheme for power MOSFETs using Embedded Power packaging technology. A liquid module test bed has been built to create various convection conditions and is used with 600-V high-current MOSFET-based Embedded Power samples to test the effectiveness and feasibility of the proposed scheme. Compared with single-sided liquid cooling, an improvement of 45% to 60% in thermal resistance is experimentally shown, for Embedded Power with double-sided liquid cooling for a device loss between 5 and 300 W and 0.25 to 4.5 GPM water flow rate. The trend and concept is also validated with physics-based lumped parameter thermal models. Index Terms--Double-sided cooling, forced liquid convection, power density, semiconductor packaging.

This paper first analyzes the electrical parameters of differential-mode (DM) and common-mode (CM) propagation on power interconnects. The impedance-transformation effects of the power interconnects are then investigated. The interactions between the parasitic parameters in electromagnetic-interference (EMI) filters and the transformed impedances by the power interconnects are explored in detail. It is found that the interactions can degrade EMI-filter performance at high frequencies. Simulations and experiments are finally carried out to verify the analysis. Index Terms--Electromagnetic-interference (EMI) filter, equivalent parallel capacitance (EPC), equivalent series inductance (ESL), impedance transformation, power interconnects, transmission line.

In this paper, thermal analysis for a 42-V/14-V bidirectional dc/dc converter with integrated inductors is performed. An interleaved dc/dc converter system with four channels was chosen for the automotive-converter topology with 42-V/14-V dual-output voltages. Coupled inductors were designed and used for the four-channel dc/dc converter. A 3-D thermal model based on finite-element modeling using I-DEAS is presented and the thermal behavior of the dc/dc converter system is simulated and analyzed. The thermal model includes a printed circuit board, integrated inductors, a heat sink, and switching devices (MOSFETs). The analyzed thermal result can help to design a converter system under severe ambient-temperature conditions. Index Terms--Bidirectional dc/dc converter, finite-element modeling (FEM), integrated inductor, thermal analysis.

In this paper, the parasitics in both differential-mode (DM) and common-mode (CM) inductors are first discussed. The methods for both DM and CM inductor winding capacitance cancellation are then proposed. Prototypes are designed and tested, using a network analyzer. Finally, the prototypes are applied to practical power converters and electromagnetic interference (EMI) is measured. Both small signal measurement and practical EMI measurement prove that the proposed methods can efficiently reduce the effects of winding capacitance and therefore improve the inductor's filtering performance. Index Terms--Electromagnetic interference (EMI) filter, EMI noise, winding capacitance, winding capacitance cancellation.

In this paper, the properties of mutual capacitance between two capacitors are first discussed. It is found that the effects of mutual capacitance can be represented by two positive or negative capacitors across the two capacitors. These two equivalent capacitors can be used to cancel the parasitic capacitance of inductors. Because the mutual capacitance can be emulated using two small capacitors, the proposed method can easily be implemented in practical components. The prototypes are then built and the cancellation is verified using a network analyzer. Further EMI measurements in a practical power circuit prove that there is a significant improvement in the inductor's filtering performance. Index Terms--Electromagnetic interference (EMI) filter, mutual capacitance, winding capacitance, winding capacitance cancellation.

Electromagnetic interference (EMI) filters have been used for power electronics converters to attenuate switching noise and meet EMI standards for a long time. However, because of the parasitics in the filters, filters cannot attenuate high-frequency noises efficiently. In this paper, critical parasitics, which include both mutual and self-parasitics, are first identified in both differential and common mode filters. Three techniques are then developed to cancel the adverse effects of mutual parasitics. These techniques can effectively cancel the inductive couplings between an inductor and capacitors, between an inductor and trace loops, and between two capacitors. Two additional techniques are further developed to cancel the self-parasitics of components, such as the equivalent series inductance of capacitors and the equivalent parallel capacitance of inductors. Experiments are carried out to verify these developed techniques. It is shown that the high-frequency performance of EMI filters is drastically improved. Index Terms--Electromagnetic interference (EMI) filter, equivalent parallel capacitance (EPC), equivalent series inductance (ESL), parasitic cancellation, parasitic coupling, self-parasitics.

The technology of integrated passive components for power electronics is at present being developed. Because of the compact structures and the special implementation techniques of these integrated modules, the high-frequency parasitic resonances are normally significant and may have a negative impact on the performance and electromagnetic interference characteristics. However, the existing modeling technique can only predict the fundamental resonant frequency and showed neither the causes of the high-frequency resonance nor how to calculate those accurately. Based on the modeling of multiconductor transmission structures, this paper presents the modeling of the spiral winding structure integrated series resonant module. This structure can be treated as several multiconductor transmission structures connected in certain patterns. Different connection patterns only determine the voltage and current boundary conditions with which the equations can be solved. The MATLAB calculation results correlate well with the small-signal measurement results. The calculation sensitivities with respect to variation of various parameters are also discussed and the causes of resonance at different frequencies are identified. Index Terms--Electromagnetic interference (EMI), integrated series resonant module (ISRM).

In integrated power modules, mechanical properties of interfaces between deposited copper traces and substrates are important for reliable operation. This paper investigates the values of thermomechanical stresses by IDEAS simulation and describes an experimental method to calculate intrinsic residual stresses using the Stoney equation based on the bending curvature of the sample. Index Terms--Intrinsic residual stress, planar metallization, thermomechanical stress.

In this paper, critical parasitic couplings in EMI filters are first identified. Based on the understanding of filter parasitics, methods are proposed to improve EMI filter performance by canceling critical couplings. A cancellation inductor is then integrated with capacitors to cancel the mutual coupling between two capacitors and the equivalent series inductance (ESL) of the integrated capacitor. The proposed method is applied to both rectangular and tubular capacitors. Two different integration approaches are also compared. Finally, prototypes are built and tested for both one-stage and two-stage EMI filters. Experimental results show the proposed mutual coupling cancellation technique can drastically improve EMI filter high frequency performance. Index Terms--Electromagnetic interference (EMI) filter, equivalent series inductance (ESL), integrated capacitor with cancellation inductor, mutual coupling cancellation, parasitic coupling.

The electromagnetic integration of multiple passive components into a single integrated planar power passive module has been shown viable, not only for resonant structures, but recently also for nonresonant applications. Recent improvements in electromagnetic design and loss modeling for a resonant integrated spiral planar power passive (IS[P.sup.3]) structures have made it possible to accurately estimate the electromagnetic characteristics of the structure before construction. In this paper, this improved modeling forms the basis of an approach for electromagnetically optimizing the structure. A graphical interface tool for identifying trends in resultant structure parameters with respect to design variables is presented. The graphical interface is also used to evaluate different possible optimization criteria. Using a simple optimization criterion, two improved prototype designs are developed and constructed. Finally, these two prototypes are then experimentally tested and compared with a prior state of the art design. These two resultant improved prototypes yield more than a doubling in structure power density without a decrease in structure efficiency. The relatively low resultant temperature differential within the prototypes shows that a substantial increase in power density is still possible and this can be effectively exploited if accurate thermal modeling is included in the future design optimization process. Index Terms--Integrated spiral planar power passive (IS[P.sup.3]), power density.

A Si CoolMOS field effect transistor and SiC diode assembly with gate driver in boost configuration (ratings at 600 V/12 A), for power factor correction application, has been fabricated in a version of an integrated power electronic module. It uses the so-called embedded power technology, to form a three-dimensional multiple chip/component interconnection with the embedded chips in a co-planar ceramic substrate with thin-film metallization bond/interconnection added on top. In this paper, the switching parameters of this module and their effects on the performance of a converter have been analyzed and experimentally characterized. The procedures adopted for the defined fabrication process of planar metallization interconnects are presented. In addition to the improvement of structural electrical properties, compared to a conventional discrete version, the characteristics of the planar process integration have also been demonstrated. Index Terms--Power electronics module integration, power semiconductor switching, structural electromagnetic parameters.

Discrete electromagnetic interference (EMI) filters have been used for power electronics converters to attenuate switching noise and meet EMI standards for many years. Because of the unavoidable structural parasitic parameters of the discrete filter components, such as equivalent parallel capacitance (EPC) of inductors and equivalent series inductance (ESL) of capacitors, the effective frequency range of the discrete filter is normally limited. Aiming at improving high frequency performance and reducing size and profile, the integrated EMI filter structure has been proposed based on advanced integration and packaging technologies [1], [2]. Some improvements have been made but further progress is limited by EPCs of the filter inductors, which is restricted by dimension, size and physical structure. In this paper, a new structural winding capacitance cancellation method for inductors is proposed. Other than trying to reduce EPCs, a conductive ground layer is embedded in the planar inductor windings and the structural capacitance between the inductor winding and this embedded layer is utilized to cancel the parasitic winding capacitance. In order to obtain the best cancellation effect, the structural winding capacitance model of the planar spiral winding structure is given and the equivalent circuit is derived. The design methodology of the layout and area of the embedded ground layer is presented. Applying this method, an improved integrated EMI filter is designed and constructed. The experimental results show that the embedded conductive layer can effectively cancel the parasitic winding capacitance, hence ideal inductor characteristics can be obtained. With the help of this embedded conductive layer, the improved EMI filter has much smaller volume and profile and much better characteristics over a wide frequency range, compared to the former integrated EMI filter and the discrete EMI filter. Index Terms--Electromagnetic interference (EMI), equivalent parallel capacitance (EPC), equivalent series inductance (ESL).

The use of embedded solid-state heat extractors to increase the power densities in power electronic modules seems promising. Cross-sectional geometric optimization was done on heat extraction insert and it was found that the most suitable heat extraction configuration for the dimensional range applicable in power electronics is the use of flat continuous heat extraction layers aiding in conducting heat to externally mounted heat sinks. Theoretically expected thermal enhancement factors were determined and experimentally verified. The adverse influence of interfacial thermal resistances on the effectiveness of heat extraction inserts was also evaluated. Index Terms--Cross-sectional geometric optimization, embedded solid-state heat extractors, externally mounted heat sinks.

Assemblies of power semiconductor switches and their associated drive circuits are at present available in modules. Upward into the multi-kilowatt range, mixed mode module construction is used. This incorporates monolithic, hybrid, surface mount, and wirebond technology. However, a close examination of the applications in motor drives and power supplies indicates that there has been no dramatic volume reduction of the subsystem. The power semiconductor modules have shrunk the power switching part of the converter, but the bulk of the subsystem volume still comprises the associated control, sensing, electromagnetic power passives (inductors, transformers, capacitors) and interconnects. This paper addresses the improvement of power processing technology through advanced integration of power electronics. The goal of a subsystem in a module necessitates this advanced integration, incorporating active switching stages, electromagnetic interference (EMI) filters, and electromagnetic power passives into modules by integration technology. The central philosophy of the technology development research in the National Science Foundation Engineering Research Center for Power Electronic Systems is to advance the state of the art by providing the concept of integrated power electronics modules (IPEMs) for all these functions. The technology underpinning such an IPEM approach is discussed. Index Terms--Electromagnetic interference (EMI) filters, integrated power electronics modules (IPEMs).

A new trend in power converters is to design planar magnetic components that aim for low profile. However, at high frequencies, ac losses induced in the planar inductor and transformer windings become significant due to the skin and proximity effects. A planar litz conductor can be constructed by dividing the wide planar conductor lengthwise into multiple strands and weaving these strands in much the same manner as one would use to construct a conventional round litz wire conductor. Each strand is then equally subjected to the magnetic fields in the winding window, thereby equalizing the flux linkage and improving the current distribution. Three-dimensional finite-element modeling was performed for simple models. The simulation results showed that the planar litz conductor can result in lower ac resistance than a solid conductor over a specific frequency range. The performance of the planar litz winding was also verified with measurements on two experimental prototypes. Index Terms--Finite-element modeling (FEM), planar litz conductor.

In most power electronics converters, the overall footprint and profile of the whole system are in large part determined by the footprint and profile of the passive components and the interconnections between them. Planar magnetics, integrated magnetics, and passive integration have been topics of research for the past few years to reduce the count, footprint, and profile of the passive components and, hence, increase the power density of the whole converter. This becomes especially prominent in distributed power system (DPS) front-end converters, as the trend is moving from the 2U (1U= 1.75 in) standard toward the 1U standard. Chen, Strydom, and van Wyk presented an integration technology, which combines the planar magnetics, integrated magnetics, and passive integration techniques, to integrate all the high-frequency passive components in a DPS front-end dc/dc converter into a single passive integrated power electronics module (IPEM) to reduce the size and volume of the overall system. To optimally design the passive IPEM, an ac loss model and a thermal model are needed. Based on these models, the volumetric optimal design algorithm is presented. To evaluate the performance of the optimally designed passive IPEM, a passive IPEM prototype is constructed and tested. Comparisons are made between the passive IPEM and the discrete components from viewpoints of volume, profile, efficiency, and thermal management. The optimal design is verified by experimental results. Index Terms--Optimal design, passive integrated power electronics module (IPEM), passive integration.

This paper treats the modeling of integrated electromagnetic power passives for integrated power electronics modules by using a distributed conductive structure approach. The distributed L-C cell is chosen as the basis for modeling. This paper presents the modeling of an L-C cell through the proposed generalized transmission structure theory that can be applied to both balanced and unbalanced current distributions. The load characteristics of a generalized transmission structure are investigated. The proposed theory has been extended to cascaded structures as well. The calculation results correlate well with the impedance measurement results. Some practical design issues are also discussed. Index Terms--Distributed inductive-capacitive structures, integrated resonant circuits, modeling of integrated electromagnetic passives.

Over the past few years, the electromagnetic integration of multiple passive components into a single integrated planar power passive module has been shown viable, not only for resonant structures, but recently also for nonresonant applications. In this paper, the development of an electromagnetic model for a resonant integrated spiral planar power passive (IS[P.sup.3]) structure is presented. For the design of the required passive component values to be integrated, a comprehensive electromagnetic model based on energy storage is presented. The overall structure losses including winding, core and dielectric losses are also estimated through the development of a partly one-dimensional electromagnetic field approximation. Finally, these electromagnetic models for design and loss estimation are compared to experimental results for three different prototypes of a particular design. The results show agreement to well within 10% of component and loss values in almost all cases. Index Terms--Core, dielectric, IS[P.sup.3], multiple passive components, one-dimensional, winding.

This paper presents a higher order frequency plane model for integrated series resonant module (ISRM). The cause for the occurring of the high frequency impedance peak is identified as the parallel resonance between the winding inductance and its inter-winding capacitance. The inter-winding capacitance can be calculated from a transmission-line-based lumped model using Schwartz-Christoffel transformation. The simulation results using the proposed model correlate the small-signal test results very well. The proposed higher order impedance model will help to evaluate the high frequency behavior of an ISRM or to minimize the high frequency parasitics. It can also be easily implemented in the design-oriented algorithm to facilitate the design and optimization of an ISRM. More simulation and experimental results will be included in the final paper. The application of this model to more complicated structures as well as some practical design issues will also be discussed. Index Terms--High frequency parasitics, ISRM, parallel resonance, Schwartz-Christoffel transformation, winding inductance.

In recent years, passive integrated power electronic modules (IPEMs), which have been implemented as resonant tanks in resonant dc-dc converters, have gained interest because of their merits for possibly reducing the total volume and improving manufacturability of the resonant converter system. However, the integration process for the passive IPEM increases the complexity of the thermal and mechanical behavior of the structure due to interactive heating of the module layers and mechanical inter-layer stresses. It is therefore essential to investigate the thermo-mechanical behavior of a passive IPEM to ensure reliable operation. In this paper, the methodology for thermo-mechanical analysis for a series resonant LC passive IPEM is developed. Especially, a three-dimensional thermo-mechanical model based on finite-element modeling is presented. The thermal analysis results were verified by an experimental prototype LC passive IPEM and temperature distribution measurement using an infrared camera and thermocouples. Results of the thermal analysis and the associated thermo-mechanical stress analysis are also discussed, illustrating the viability of the methodology developed for thermally induced mechanical stresses. Index Terms--Finite-element modeling (FEM), passive integrated power electronic module (IPEM), thermo-mechanical stress analysis.

A metal-oxide-semiconductor field-effect transistor (MOSFET) (rating at 500 V/24 A) half-bridge power switching subassembly with gate drivers has been fabricated, employing a planar integration technology, in which an integrated power chips stage is built by embedding chips in a coplanar ceramic substrate with a metallization thin-film interconnection built up onto it. This deposited metallization not only bonds the power chips, but also provides the second-level interconnect wiring. The associated components are mounted on top of the integrated power stage. This packaging scheme results in a three-dimensional (3-D) multiple chips/components assembly with the capability of functional integration. In this paper, the electrical and thermal parameters of this packaged module have been experimentally and theoretically characterized. The procedures adopted for the defined fabrication processes are presented. In addition to the characteristics of the planar integration process, the improved electrical and thermal performance has been demonstrated. Index Terms--Multichip 3-D integration, planar process technology, power electronics integrated packaging, power electronics modules.

Integrated inductor-inductor-capacitor-transformer (L-L-C-T) technology has been the subject of intensive research over the last few years. Its application to resonant power electronics converters has been reported in many previous publications. This paper presents the application of a planar L-L-C-T module to the integration of passive module for a zero-voltage-switched (ZVS) asymmetrical half-bridge pulsewidth-modulation converter (AHBC) for application in a distributed power system. Two output transformers, two current-doubler inductors, the ZVS resonant inductor, and the transformer dc decoupling capacitor are integrated into a single module. The design procedure is discussed and some special considerations of the L-L-C-T module in nonresonant applications are addressed. A 1-kW 300 V-400-V input 48-V output AHBC employing the L-L-C-T module is constructed. A comparison of the AHBC using the integrated passive module and the same circuit using discrete components is given. Index Terms--Asymmetrical half-bridge pulsewidth modulation (PWM) converter (AHBC), distributed power system (DPS), electromagnetic passive integration, inductor--inductor--capacitor--transformer (L-L-C-T).

An alternative approach to construct a planar integrated reactive power module is presented in this paper. Enclosed in a planar core, a few copper strips plated on both sides of a high-permittivity ceramic substrate generate a series of so-called L-C cells. Various equivalent circuits may be realized with this chip-like module using different printed circuit board PCB interconnections between the L-C cells. The experimental results show its potential as an integrated high-frequency power resonator. Good correspondence between experimental measurement and first-order models is demonstrated. Index Terms--integrated reactive power modules, multicell structure, passives integration.

The operation of power semiconductor modules creates thermal stresses that grow voids in the solder die-attach layer. These voids reduce the ability of the die-attach solder layer to conduct heat from the silicon junction to the heat spreader. This results in increased thermal impedance. The effect of accelerated aging on solder bond voiding and on thermal transient behavior is investigated. Commercially packaged TO-247 style MOSFETs are power cycled, imaged, and thermally analyzed to generate a correlation between void percentage and thermal impedance. Index Terms--Die-attach, power MOSFET, thermal impedance, thermal resistance.

A hybrid power compensator (HPC) consisting of a static var compensator and a dynamic compensator needs to be optimally controlled during the compensation of nonlinear loads. The HPC must be controlled to meet minimum requirements in terms of power factor and harmonic distortion, while at the same time minimizing its total cost. An artificial neural network (ANN) is used to control the HPC amidst a very dynamic power system environment. The performance of a reference ANN is evaluated while controlling an HPC connected to a typical nonlinear industrial load. The training and performance of the ANN is then optimized in terms of training set size, training set packing and ANN topology and the performance compared to the reference ANN. This paper highlights the importance of optimising the mentioned ANN parameters to achieve optimum ANN training and modeling accuracy. The results obtained reveals that the application of an ANN in controlling an HPC is feasible given that the ANN parameters are chosen appropriately. Index Terms--Artificial neural network (ANN), compensator, hybrid, optimization, power, system, training.

The integrated planar resonant/transformer structures analyzed are constructed from planar ferrites, conductive layers, leakage layers and ceramic dielectric substrates. The minimum dimensions for these electromagnetically integrated structures are determined based on electromagnetic and technological limits respectively. Thus to answer the question as to what is the minimum required volume that can be theoretically achieved, the electromagnetic material limits are analyzed. These material limits are expressed in terms of the permeabilities, permittivities and conductivities, skin effect and breakdown field of the different materials. A design based solely on these electromagnetic limits is developed and compared to the present constructional limitations. This is conducted for an example of a particular integrated resonant/transformer structure, the L-L-C-T, to illustrate the analysis. This analysis indicates that design based on the electromagnetic limits results in volumes two orders of magnitude smaller than the present prototypes, illustrating that the power density is at present only limited by constructional technology. The thermal limit, however, is expected to be the next barrier within one order of magnitude. Index Terms--Hybrid converters, integrated capacitance--inductance, passive integration, volumetric limits.

This paper covers the experimental investigation and theoretical calculation of losses in a planar inductor under load. Finite-element software is used to perform the loss calculations. Thermally controlled experiments are performed for a range of frequencies to validate the corresponding finite-element method loss calculations. The thermal dependence of the loss mechanisms is also considered. Index Terms--Finite-element method (FEM) calculations, loss analysis, loss measurement, planar inductor, thermal measurement.

A hybrid power compensator (HPC) consisting of a static var compensator and a dynamic compensator needs to be optimally controlled during the compensation of nonlinear loads. The HPC must be controlled to meet minimum requirements in terms of power factor and harmonic distortion, while at the same time minimizing its total cost. The use of an artificial neural network (ANN) to control the HPC amid a very dynamic environment to achieve the above is investigated. A state-space model of the power distribution network together with the HPC forms the basis of evaluation of the mentioned controller. The model was calibrated against actual in-network measurements. The results obtained reveals that the application of an ANN in controlling an HPC is feasible given that the ANN parameters are chosen appropriately. Index Terms--Artificial neural network, hybrid power compensator, optimal control, power system, state-space model.

Contactless power delivery systems for mobile loads use transformers comprised of a core with a secondary winding sliding along an extended primary winding. The sliding transformer is identified as the most limiting component in the system and is analyzed by representing it as a special, multiturn power transmission line. Two performance parameters, namely, the transmission line efficiency and system penalty factor, are introduced. It is shown that fundamental restrictions may limit the attainable performance of the system. The inductance of the primary winding is identified as a parameter which can be optimized to improve the system performance. Experimental results for a short- and a long-stroke transformer are presented. Index Terms - Contactless power transfer, linear transformers, medium-frequency inductive power transfer.

High-voltage acceptor-doped barium-titanate ceramic capacitors are suitable for hybrid planar-integration of power-electronic converters. The dielectric material is useful in high-permittivity sub-structures at low fields and sub-structures with strong voltage-dependent permittivity at higher fields. The study designs a ceramic material suitable for nearly-constant tan-delta and permittivity of up to 1 MHz.

In this paper methods of design and application of integrated inductor-capacitor-transformer (LCT) are presented. A generalized modeling approach is also described. On the basis of this model and by using practical data, a CAD software is developed for LCT. Several integrated LC and LCT samples were designed, built, and tested. Finally, a resonant converter, using integrated LCT, was built and tested.

Integrated inductor--capacitor-transformer L-C-T technology has been the subject of research over the last few years. Research into producing optimum design equations has been conducted. To determine some of the physical and technological limitations of the integrated L-C-T technology, a 1-kW 1-MHz resonant dc-dc converter was designed and built. The design was limited only by in-house material, construction, and technological restrictions. Through this process, it is hoped that some of the current technological limitations can be quantified. The design and construction process is given, while some of the limits of this technology are derived from experimental results. Index Terms--Hybrid converters, integrated capacitance-inductance, passive integration, resonant converters.

Capacitors are utilized in a variety of different ways in power electronic circuits. Typical applications are in snubber, clamping, and resonant circuits. For design purposes, it is necessary to make an accurate measurement of the actual behavior of the capacitance that is added to the circuit under conditions related to those prevailing in a converter. For this purpose, a number of different measurement systems or techniques can be utilized. Four of these measurement systems are compared. These are small-signal variable-frequency measurement, large-signal quasi-dc measurement, in--situ high-voltage measurement, and small-signal with large dc bias voltage measurement. Each of these measurement techniques returns characteristic values based on its particular model of the test capacitor. These tests are done on both ceramic and nonceramic capacitors at room temperature. The results are discussed. Index Terms--Capacitor measurement, dielectric measurement, in--situ measurement, large-signal measurement.

This paper evaluates the error in compensation due to two main limitations. The first limitation is the lagging of the compensation reference caused by the sampling and processing due to digital signal processing equipment. The second limitation is the di/dt capability of the switching converter. Models are derived to evaluate the error due to these two limitations, as well as the percentage contribution to the total ineffectivity of compensation. Experimental results confirm that the mentioned limitation that has the most detrimental effect on compensation can easily be determined with the use of the models derived in this paper. Index Terms--Active filters, compensation, delay effects, digital signal processing.

In this paper three different methods of power resolution, namely that of Budeanu, Czarnecki and the IEEE Working Group, are compared for practical utility. In order to study alternative compensation schemes for a large industrial plant, a steady-state harmonic penetration model has been developed on a Mathcad package. Three different interpretations are chosen with which to carry out this study, namely those of: Budeanu, the IEEE Working Group and Czarnecki. The different interpretations are analyzed with the Mathcad model in a search for an optimal compensating topology. The paper begins with a general investigation into distortion power analysis, which is then extended to the above approaches. It concludes with a discussion in which the practical utility of the different power analyzes is compared to each other in an industrial environment. The conclusions drawn are that the Budeanu method gives erroneous results in the presence of certain kinds of distortion and that the Czarnecki approach is complex and new to industrial users. Use of the IEEE Working Group approach is encouraged because it is merely an extension of the classic sinusoidal definitions that are already well understood. Index Terms--Budeanu, Czarnecki, IEEE working group, power definitions, power theories, practical plant.

This paper presents the design of a high-power-density igniter with integrated LC resonator for low-wattage high-intensity discharge lamp ballasts. Electromagnetic integration technology is applied to reduce the number of passive components and the overall volume of the igniter. By applying the interwinding capacitance as the resonant capacitance, the integrated igniter is simply composed of a magnetic core and two magnet wire windings. By selecting the proper terminals and exploiting the advantage of an integrated LC resonant structure, the obtained output voltage is twice as much as an ordinary LC resonator. The design and implementation of the igniter are presented, while the experimental results of a small-signal measurement and a high-voltage test are given. The experiment results show that the application of passive integration technology into low-wattage passive modules is promising. [ABSTRACT FROM AUTHOR]

A low-profile power inductor fabricated using low-temperature cofired ceramic (LTCC) technology has been demonstrated to improve the light-load efficiency of a converter, without the use of additional control circuitry. This is brought about by the material and the geometry, which causes a change in inductance with load current. Variation in inductor geometry is performed experimentally to study the effects on the light-load efficiency of a converter. By decreasing the conductor width of the inductor, the light-load efficiency can be further improved by 30% in comparison with using commercial inductors of similar inductance. Sufficient core thickness is necessary to have sufficient inductance, since an inductance value which is too low is detrimental from the system power loss point of view, as demonstrated experimentally. From the circuit point of view, there seems to be a critical inductance value, whereby increasing the inductance further, does not result in significant improvement in power stage efficiency. Changing conductor thickness in the range of 260 to 550 μm does not result in significant improvement in the overall efficiency of the converter. Variation in the number of parallel conductors in a multiconductor structure does not have significant effect on light-load efficiency improvement. [ABSTRACT FROM AUTHOR]

In this paper, effects of parasitic parameters on the electromagnetic interference (EMI) filter performance are first discussed. The parasitic cancellation techniques for both self- and mutual parasitics are then reviewed and their constraints are identified. The possibilities of integrating parasitic cancellation techniques into one EMI filter are analyzed. It is found that three parasitic cancellation techniques can be integrated into one EMI filter to improve both differential-mode and common-mode filter performances without any conflicts and compromises. Experiments are finally carried out to verify the integration of these three cancellation techniques. [ABSTRACT FROM AUTHOR]