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This article puts forward a hybrid model predictive control (H-MPC) for an inner-interleaved hybrid multilevel converter (IHMC). The sign patterns of the original and shifted reference vectors in the original and virtual space vector diagrams (VSVDs) are used, respectively, to realize the phase-disposition pulsewidth modulation (PWM) and determine the low-frequency switching states. Then, the three adjacent vectors are selected in the second-layer VSVD and the optimal current tracking is safeguarded by the duty cycle optimization of the three adjacent vectors. Finally, through applying the phase-shifted PWM to the two interleaved legs, a constant and doubled equivalent switching frequency can be achieved, which further paves the way for dc-link and floating capacitor voltages balancing and circulating current mitigation with the use of the straightforward duty cycle adjustments. The proposed H-MPC enables the decoupling of the low- and high-frequency stages in the IHMC and also reduces both output current ripples and computational burden while achieving a constant switching frequency simultaneously. Comprehensive simulation and experimental studies on an all silicon carbide prototype verify the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Power module heat dissipation with spatial inhomogeneity and induced nonuniform temperature distribution presents a challenging concern for system reliability due to thermo-mechanical stresses. These reliability challenges are especially important for nonplanar designs using 3-D packaging principles. Here, we develop a heat spreader thermal switch capable of actively reducing temperature gradients between silicon carbide (SiC) devices in a three-level T-type power converter, which can change depending on electronic operating conditions. The heat spreader thermal switch consists of a stainless-steel (SS) heat spreader and a copper sliding switch embedded within the spreader. Heat transfer from the SiC devices and within the spreader can be controlled by moving the slider between positions within the spreader. To understand heat transfer mechanisms and design the heat spreader thermal switch, we conducted 3-D finite element method simulations to calculate the minimum attainable temperature difference between SiC devices. We used the finite element simulation to quantify the reduction in junction temperature swing during dynamic operation and coupled the results to the Coffin–Manson reliability model to quantify lifetime to failure. We integrated the heat spreader thermal switch with one phase of a three-phase T-type converter and demonstrated isothermalization at different working conditions. At 2.4-kW converter power, each hot SiC device dissipated 4.7 W of heat, resulting in a device case temperature of 43 °C, with each cold SiC device dissipating 1.7 W at 38 °C. The device-to-device temperature difference was decreased from 5 °C to 0 °C by moving the switch a distance of 20 mm. Finite volume method (FVM) simulations of the conjugate heat transfer problem validate the experimental results and support analysis of key performance parameters. This work demonstrates successful isothermalization of a power converter with an active heat spreader thermal switch and develops simulation and design guidelines for successful electro-thermal codesign and implementation of thermal switches for other electronics applications for which isothermalization and enhanced device reliability is a key issue. [ABSTRACT FROM AUTHOR]

A series of novel externally reconfigurable power electronic modules (RPEMs) are invented to increase the flexibility of power modules and their application purposes. In this article, the concept of RPEMs, their switching arrangements, and power-module-based architectural design are demonstrated. An RPEM is then designed, analyzed through simulations, and compared with the conventional fixed-configuration power electronic modules. The sizes of the power modules and used power terminals are kept similar to avoid any differences in power loop inductance values solely due to various trace pad sizes. In addition, similar gate/source pads and signal pins are used for all of the designed power modules to have constant switching dynamics in all modules. The comparison results show that the internal parasitic inductance and performance are still comparable with the conventional modules despite having high configurability. The designed RPEM and a conventional full-bridge (FB) power module are fabricated and characterized. The experimental tests show that the difference between the overshoot voltages on both RPEM and FB power modules is less than 2%. Such flexibility without compromising the power module performance decreases the engineering time for designing different power modules for various power electronic converters; hence, the production speed can be improved while decreasing the overall module cost. [ABSTRACT FROM AUTHOR]

This article presents the design and demonstration of an all silicon carbide (SiC) 2×250 kW dual inverter for heavy-duty traction applications. Through the use of a formal electrothermal-control co-design approach, the maximum power density of the proposed inverter system is 60 kW/L, which is accomplished by. More specifically, to analyze the thermal performance of the inverter, a lumped thermal model is developed based on the characteristics of the power modules and the cold plate. To analyze the complicated interaction between the power losses and module junction temperatures, a closed-loop iterative estimation scheme is proposed to estimate the inverter power loss and module junction temperature. Based on the proposed thermal model and estimation scheme, a detailed optimization procedure on the selection of switching frequency and dc-link capacitor is presented to maximize power density. Furthermore, design optimization of the busbar was conducted to minimize the stray inductance, thus reducing the voltage overshoot during switching transients. Comprehensive experimental studies were performed on a physical converter prototype built based on the optimization results, which validate both the effectiveness of the presented design approach. [ABSTRACT FROM AUTHOR]

A comprehensive overview of the advancements, challenges, and prospects of silicon carbide (SiC) complementary metal-oxide-semiconductor (CMOS) technology is presented. As the demand for high-performance and energy-efficient electronic devices continues to grow, SiC has emerged as a promising material due to its unique properties. The paper aims to provide a thorough understanding of the state-of-the-art developments in SiC CMOS technology. The paper delves into the key features of SiC and its compatibility with CMOS processing techniques. It highlights the challenges associated with SiC CMOS technology, such as substrate quality, interface states, and process integration. Examples of CMOS circuitry that have been successfully designed, fabricated, and tested are provided. [ABSTRACT FROM AUTHOR]