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This paper evaluates the capability of SiC power semiconductor devices, in particular JFET and Schottky barrier diodes (SBD) for application in high-temperature power electronics. SiC JFETs and SBDs were packaged in high temperature packages to measure the dc characteristics of these SiC devices at ambient temperatures ranging from 25 °C (room temperature) up to 450 °C. The results show that both devices can operate at 450 °C, which is impossible for conventional Si devices, at the expense of significant derating. The current capability of the SiC SBD does not change with temperature, but as expected the JFET current decreases with rising temperatures. A 100V, 25W dc-dc converter is used as an example of a high-temperature power-electronics circuit because of circuit simplicity. The converter is designed and built in accordance with the static characteristics of the SiC devices measured under extremely high ambient temperatures, and then tested up to an ambient temperature of 400 °C. The conduction loss of the SiC JFET increases slightly with increasing temperatures, as predicted from its dc characteristics, but its switching characteristics hardly change. Thus, SiC devices are well suited for operation in harsh temperature environments like aerospace and automotive applications. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical analysis for canceling common-mode (CM) voltages for induction motor (IM) drives using a CM transformer with active circuitry. The design methodology and the practical implementation are presented for motor drives rated 460 V or higher. To verify the design approach, an implementation example and experimental results for a 460-V motor drive system are presented. [ABSTRACT FROM AUTHOR]

The use of environmentally clean photovoltaic (PV) dispersed generation will become more widespread in the future due to anticipated cost reductions in PV technology. This paper summarizes the results of a power quality (PQ) study performed on a PV generator in order to estimate the effects that inverter-interfaced PV dispersed generation might have upon the quality of electric power. Different interpretations of the harmonic distortion limits set in the IEEE 519-1992 standard are performed together with a comparison with the BC Hydro's harmonic current limits. This paper also includes a statistical analysis of all measurements recorded with the help of two PQ monitors, an evaluation of the results from a connection/disconnection test, and harmonic simulation results. [ABSTRACT FROM AUTHOR]

Presents a study which proposed a methodology to determine separately the peak and continuous power ratings of a switched reluctance motor (SRM) for electric propulsion of an electric vehicle (EV). Procedure for sizing the SRM; SRM loss trends; Comparison of SRM with other EV electric motors.

Multilevel dc-dc converters making use of high- frequency transformers are suitable for integration in solid-state solutions for applications in electric power distribution systems. This paper presents a simplified switching scheme for three-level full-bridge dc-dc converters that enables zero-voltage and zero-current switching of all the main power devices. It describes the main operational moden and design equations of the converter as well as provides simulation and experimental results to demonstrate the feasibility oft he proposed ideas. [ABSTRACT FROM AUTHOR]

Distributed energy resources (DERs) are becoming integral components of electric power distribution systems. Inmost cases, an isolated dc-dc converter forms part of the interface required to connect the DER output to the distribution system. Operation of the converter at high switching frequencies results in size reduction of passive components at the expense of increased switching losses. However, silicon carbide (SiC) power devices have the potential of operating at high switching frequencies without significant loss penalty because of their fast switching times and ability to work at high temperatures when compared to similar Si devices. SiC diodes have already displayed the ability to offer more ideal diode behavior than Si diodes. Engineering samples of SiC MOSFETs are depicting lower switching losses and conduction losses over Si MOSFETs. This display is making SiC devices attractive for dc-dc converters used to connect DERs to the distribution system. This paper particularly deals with the design of a 300.W 100-kHz dc-dc full-bridge converter using zero-voltage zero-current switching for comparison of SiC MOSFETs and diodes against Si MOSFETs and diodes. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method to generate a sinusoidal waveform synchronized with any measurable pearidge signal whose frequency is within a given neighborhood. The synthesized sinusoidal signal could be used as a reference current for certain applications of parallel active power filters or any other where such synchronization would be necessary (e.g., ac/dc converters for renewable energy resources, power factor correctors, power supplies, UPS, etc.) The method is based on the behavior of a dynamical system and avoids employing the usual combination of phase-locked loop (PLL) and lookup table found in most parallel active filters synthesizing a sinusoidal source current (a table also means using significant storage memory). The novel method produces two high-quality sinusoidal waveforms that are in quadrature and is applicable to those parallel active filters whose control methodology is in the αβ reference frame, or alternatively, it produces three sinusoidal waveforms shifted 120 degrees for designs that work in the abc frame. Here, a (2n + 1)th order implementation is described, including a proof of convergence. For its most simple implementation (n = 1), simulated and experimental results are included. [ABSTRACT FROM AUTHOR]

As a high-efficiency converter for photovoltaic power generation, the integrated boost series resonant (IBSR) converter includes three inductors, two capacitors, and one transformer, which occupy a significant volume. In order to further increase the power density, this paper proposes a novel passive integrated unit with the flexible multilayer foil integration technique for the above six passive components. First of all, the distributed electromagnetic component model of one new flexible three-layer film shows that the distributed parasitic capacitors formed by the insulation film are combined into the resonant capacitance. Then, the configuration of the proposed integrated unit is described in detail, and the electromagnetic analysis is given. Furthermore, the design procedure for the proposed integrated unit is demonstrated. Finally, a prototype for a 350 W IBSR converter has been built and the experimental results prove the validity of the proposed idea. [ABSTRACT FROM AUTHOR]

The derivation and implementation of the natural switching surfaces (NSS) considering certain parametric uncertainties for a flyback converter operating in the boundary conduction mode is the main focus of this paper. The NSS with nominal parameters presents many benefits for the control of nonlinear systems; for example, fast transient response under load-changing conditions. However, the performance worsens considerably when the converter actual parameters are different from the ones used in the design process. Therefore, a novel control strategy for NSS considering the effects of parameter uncertainties is proposed. This control law can estimate and adapt the control trajectories in a minimum number of switching cycles to obtain excellent performances even under extreme parameter uncertainties. The analytical derivation of the proposed adaptive switching surfaces is presented together with simulations and experimental results showing adequate performance under different tests, including comparisons with a standard PI controller. [ABSTRACT FROM AUTHOR]

• Development of lightweight polymer additively manufactured manifolds for electronics cooling. • Thermofluidic performance impact of rectangular, zig-zag and serpentine channels having a variety of hydraulic diameters is studied. • Conventional design approaches compared with 2D topology optimized designs. • Zig-zag designs showed the best performance among conventional designs considering the combined effects of thermal and hydraulic parameters giving 0.93 (cm2·K)/W at 2.4 kPa. • Topology optimized designs outperformed conventional designs with 1.1 (cm2·K)/W at 0.8 kPa. Single-phase liquid-cooled heat sinks are a preferred mode of thermal management for many power dense electronic applications. This paper studies the design, optimization, and thermal-hydraulic performance of polymer manifolds directing coolant to the base plate of multi-chip power modules. Direct cooling eliminates the need for thermal interface materials which form a major bottleneck to junction-to-coolant thermal resistance reduction in state-of-the-art metallic cold plates. We use 2D topology optimization (TO) to develop designs using side view (SVTO) and top view (TVTO) sections of the flow domain in contact with the power module base plate. We also use 3D TO design (CTO) which combines SCTO and TVTO. The TO designs are compared against conventional mini-channel designs including rectangular, zig-zag and serpentine channels. Cooling performance of the different designs is computed using computational fluid dynamic (CFD) simulations. Experimental quantification is achieved through measurements of the silicon carbide device junction temperature and inter-device temperature difference along with the pressure drop influencing the pumping power requirement. The CFD simulations were used to identify optimized manifold designs which were fabricated using selective laser sintering of PA12 and validated experimentally using surrogate heaters. Zig-zag designs showed the best performance among the conventional designs (0.93 (cm2·K)/W), at the cost of high pressure drop (> 2.4 kPa). Serpentine channel designs were effective in limiting inter-device temperature difference (< 0.26⁰C) through multiple changes of flow direction. The TO designs improved the performance (1.1 (cm2·K)/W) when compared against conventional channels showing lower maximum temperatures with lower pressure drops (0.8 kPa). Fluid manifolds are shown to greatly influence the coolant flow field, leading to flow maldistribution with low velocity pockets, emphasizing the need for optimizing the complete manifold design. [Display omitted] [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) semiconductors are becoming the preferable choice over silicon (Si) semiconductors for power converter applications within the 200 V to 1.2 kV range due to their superior performances. Indirect matrix converters (IMCs) have more potential than traditional back-to-back power converters (BBCs) for achieving higher power densities and longer equipment lifetimes. This paper combines normally off SiC JFETs and the IMC topology to develop a module-based IMC system whose power stage consists of a bidirectional rectifier power module (BPM) and an inverter power module. This combination achieves a power density of approximately 72 kVA/L at the module level. A 5-kVA IMC prototype operating at a switching frequency of 30 kHz and connected to an RL load demonstrates the functionality of the proposed modular IMC system. [ABSTRACT FROM AUTHOR]