Remaining useful lifetime prediction and extension of Si power devices have been studied extensively. SiC power devices have been developed and commercialized. Specifically, SiC MOSFETs have been utilized for the next generation high-voltage, high-power converters with smaller size and higher efficiency, covering various mainstream applications, including photovoltaic systems, electric vehicles, solid-state transformers, more electric ships and airplanes. However, the SiC-based devices have different failure modes and mechanisms compared with Si counterparts. Therefore, a comprehensive review is critical to develop accurate lifetime prediction and extension strategies for SiC power converter systems. The SiC power device component level failure modes and mechanisms are first investigated. Different accelerated lifetime tests and component level lifetime models are then compared. Power converter system level offline lifetime modeling techniques and software tools are further summarized. Besides, the SiC power converter condition monitoring strategies and health indicators are surveyed. The online measurement challenges are also studied. Furthermore, the system level lifetime extension strategies are reviewed. By integrating device physics, statistical modeling, reliability engineering, mechanical engineering with power electronics, this paper is intended to provide a comprehensive overview, address existing challenges, and unfold new research opportunities regarding the SiC power converter real-time lifetime prediction and extension.

The temperature-dependent characteristics of the latest generation 10 kV/20 A SiC MOSFET including the static characteristics and switching performance are carried out in this paper. The steady-state characteristics, including saturation current, output characteristics, anti-parallel diode and parasitic capacitance, are tested. A double pulse test platform is constructed including a circuit breaker and gate drive of the 10 kV MOSFET with >10 kV insulation and also a hot plate under the device under test for temperature-dependent characterization during switching transients. The switching performance is tested under various load currents and gate resistances at a 7 kV dc-link voltage from 25 °C to 125 °C. A simple behavioral model with its parameter extraction method is proposed to predict the temperature-dependent characteristics of the 10 kV MOSFET. The switching speed limitations, including the reverse recovery of SiC MOSFET's body diode, over-voltage caused by stray inductance, cross-talk, heat sink and electromagnetic interference (EMI) to the control are discussed based on simulations and experimental results.

DC circuit breakers (DCCBs) play a significant role in obtaining the reliability and stability of DC power systems. Selective and fast isolating of faults minimizes the power supply outages to end electricity users and protects the power converters implemented in the DC system. During the last decades, DCCBs have been deeply investigated in industry and academia. There has been impressive progress in terms of efficiency, response time, power-density, lifetime, and electrical operating ratings. Introducing wide bandgap (WBG) devices further has motivated researchers to propose more efficient and novel topologies. This paper provides a point of reference and a background review for DCCBs from novel aspects, fulfilling absent parts in the literature. The elaborated subjects include current commutation circuitry, DCCBs trip-curves developments, newly added functions to DCCBs, as well as marketing analysis. The advancements of DCCBs are surveyed and development needs are recognized. This paper aims to identify the future research needs of DCCBs for emerging DC power systems.

This article presents six groups of dynamic temperature-sensitive electrical parameters (TSEPs) for the medium-voltage silicon carbide (SiC) and silicon (Si) devices. The physical mechanisms of the temperature dependence of these parameters are analyzed with the difference between SiC and Si devices highlighted. A test platform is developed that enables implementation of the temperature relevant dynamic characterization. The investigated TSEPs are summarized in terms of their relationship with junction temperature, load current, dc voltage, and external gate resistance. The impact of the parasitic parameters on the evaluation results is analyzed. The comparison between 3.3-kV 5-A SiC MOSFETs and 3-kV 12-A Si insulated-gate bipolar transistors (IGBTs) is conducted. The results verify that for the medium-voltage SiC MOSFETs, the turn-off drain–source voltage switching rate, the turn-off gate current peak value, and the turn-on gate current plateau achieve better thermal sensitivity, in comparison with the Si IGBTs. The turn-off and turn-on delay time exhibit better thermal linearity compared with other investigated TSEPs.

The ability to concurrently power multiple loads has been a new feature for the inductive power transfer (IPT) system in more applications, such as the gate driver powering in the modular multilevel converter. As one of the applicable configurations, the domino-type IPT system cannot only transfer power over a longer distance but also achieves load-independent outputs. This article reviews the existing multiple-load IPT systems and aims to provide a methodology to systematically construct suitable domino-type IPT topologies with multiple load-independent constant-current (CC) or constant-voltage (CV) outputs. There are three innovative contributions. First, three kinds of resonant circuits are summarized to achieve the compensation network, including the series–series, T-type, and Π-type topologies. Second, nine CC and nine CV topologies are proposed, analyzed, and evaluated as candidates for various applications. The optimal CC and CV topologies are identified, and the integrated magnetic coupler designs are provided accordingly. Third, the power transfer capability is investigated, considering the parasitic resistances of passive components. The attenuation of load currents/voltages and the system efficiency relationship with load resistance, coupling coefficient k , quality factor Q , and load number N are analyzed, providing the guideline to design the load-independent domino system with high system efficiency. A single-input-four-output domino-type IPT system is implemented to validate the effectiveness of the proposed design methodology. Experimental results have shown consistency with the analysis results, and the efficiency can reach 89.79% when k = 0.193, Q = 320, and N = 4.

This article introduces a 4 kV/120 A solid-state dc circuit breaker (DCCB) based on discrete SiC mosfets. The DCCB is designed in a five-layer tower structure. Each layer consists of a circular main conduction branch and an attached gate driver. There are two primary benefits of the proposed DCCB. First, it reduces conduction loss with multiple devices in parallel. Second, it achieves an ultrafast response speed with SiC mosfets. Moreover, the gate drivers of the DCCB are powered by a domino inductive power transfer (IPT) system. It achieves the load-independent constant-voltage output characteristics, which means the outputs are immune to load variations. An IPT system prototype is implemented to test the power transfer performance. At 500-kHz frequency, the total output power reaches 15.73 W, which is sufficient to power on five gate drivers, with a peak transfer efficiency of 75.4%. The IPT system is tested to power a 4 kV/120 A DCCB prototype. It validates that the DCCB is effective to turn off 120 A current within 3.5 μs.