With increasing applications of silicon carbide (SiC) power MOSFETs, more attention is being paid to reliability issues, among which the long-term stability gate threshold voltage paramount importance. In this study, laboratory experiments are conducted investigate instability under AC stresses with different duty ratios, and on & off-state voltages. It found that no prominent drift would occur even for bipolar stresses, as long within (higher than) critical negative bias related device...

For silicon carbide (SiC) power MOSFETs, threshold voltage drift is a remaining obstacle in their way to the market. This study experimentally investigates under dynamic or switching gate stresses. It shown that, beside static stress, events can themselves be driving force of drift. However, this happens only when stress bipolar. The extends show that induced sustained. findings used further work for managing and coping with device applications.

Silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors (MOSFETs) are regarded as the key device for next generation of power electronics. However, wide applications hindered by threshold voltage instability. How drifts under both static and dynamic gate stress has been reported. But underpinning mechanism remains to be revealed, which is basis exploration application solutions. This letter investigate why drifts. It found that local electric field plays role behind...

Four-mode modulation (FMM) method is the most advanced for four-switch buck–boost converter among existing control strategies. But its efficiency still not optimal. In this article, all FMM methods are analyzed, and minimum inductor current root mean square value of each obtained via generalized Lagrange multiplier method. Under circumstance, optimal selected to form a that improves operating over whole range. Experimental results comparison with state-of-the-art demonstrate effectiveness...

Owing to the superior performances, silicon carbide (SiC) metal oxide semiconductor field effect transistors ( <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s) attract a lot of attention. To increase power density, it is desired use third quadrant (3rd-quad) characteristics rather than externally paralleled Schottky diode for freewheeling during deadtime. It has been known that 3rd-quad far more body diode, and MOS channel also...

Parallel devices in nonuniform conditions can easily lead to reduced overall reliability or even failure due uneven energy distribution. Especially under long-term avalanche stresses, the degradation of device may have a great impact on electrical parameters and performance. To study tendency aging mechanism parallel-connected silicon carbide (SiC) MOSFET, repetitive unclamped inductive switching (UIS) experiments are carried out this article. Technology computer-aided design (TCAD)...

A concern with the isolation transformer in a dual active bridge (DAB) dc–dc converter is dc bias magnetization. This article proposes fluxgate-based current sensor to measure component mixed large, high-frequency ac current. Compared commercial Hall effect sensor, proposed significantly reduces measurement error. presents working principle and design considerations. prototype demonstrated for elimination control DAB converter.

Modular multilevel converters (MMCs) are widely used in grid scale power electronics. Due to the presence of a dc component arm current, MMC submodules (SMs) show an unbalanced current loading profile. This may lead some semiconductor chips being more stressed than others, significantly affecting overall reliability. To level junction temperatures and improve SM reliability, this article proposes asymmetrical module design line with profile, allocating higher parts. is shown be realistic if...

In dc microgrid, the cascaded system has been extensively employed. However, negative impedance characteristics of converter may induce instability. This article proposes an optimized parallel virtual resistance (PVR) based active damping control to improve stability cascade in microgrid. The advantage this method is that it not only meets closed-loop dynamic performance source (SC), but also requirements matching input load converter. range PVR under full and its influence on output SC are...

DC bias in a transformer is threat to the safe and efficient operation of dual active bridge (DAB) converters. Detecting dc component milliamperes mixed with large ac current difficult. This article proposes sensor based on magnetic flux (MF) cancellation. The proposed utilizes (CT) extract measured current. Then, power op-amp copies CT signal an additional winding generate MF opposite that main Hence, range required measure greatly reduced for much smaller absolute measurement error. Using...

Transformerless grid-connected inverters are widely applied due to their low cost and small volume. But the dc current injection (DCI) is one of main problems that need be solved. It difficult measure milliamperes mixed in large (≥10 A peak) ac current, which causes it suppress DCI using ordinary sensor (CS). To solve this problem, a novel CS proposed. uses transformer (CT), power amplifier, an additional winding cancel magnetic field commercial (CCS). Under circumstance, CCS used detect...

Silicon carbide (SiC) power MOSFETs are gradually being put into the market due to their superior performance, and threshold voltage instability issues during long-term operation attract electrical engineer's attention. In this conference, drift caused by dynamic gate stress at room temperature high is investigated. Besides, effects of with different duty cycles on experimentally studied. It found that a more negative observed temperatures compared temperature. Moreover, cycle only affects...

The modular multilevel converter (MMC) is developing rapidly as a key technology for future grid applications. Submodule capacitor reliability major concern. Among these problems, failures accounted about one-third. Therefore, it meaningful to monitor the aging of and determine when change it. In this paper, condition monitoring method proposed record real-time IGBT switching frequencies compared with their initial values. With Back Propagation Neural Network (BPNN), relationship between...

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This letter deals with a single-phase, nonisolated on-board charger (OBC) for electric vehicles (EVs) based on four-switch three-port (FSTP) converter topology power decoupling function. However, in the published literature, size of cell (inductor and capacitor) is generally large, making promotion application challenging. To minimize size, an improved control method proposed this letter. Specifically, inductor current reference value generated by using output proportional integral (PI) plus...

A potential concern with the isolation transformer in a dual active bridge DC-DC converter (DAB) unit is DC bias of magnetization. With influence bias, loss increases, and lifespan decreases. However, it difficult to accurately measure small component mixed large (>10A peak), high-frequency AC current, which makes eliminate bias. novel sensor proposed solve this problem. The based on principle single-core fluxgate current transformer. Compared an ordinary Hall effect sensor, significantly...

The voltage spikes generated by the turn-off of high-speed switches can easily drive devices into an avalanche mode and even failure. In order to study silicon carbide (SiC) MOSFET"s limit a single device influence electrical parameters paralleled devices, unclamped inductance switching (UIS) test platform for SiC MOSFETs is set up. This paper summarizes single-pulse MOSFET under different inductances temperatures through experiments. addition, characteristics parallel connected are also...

Abstract To reduce the power loss in a modular multilevel converter (MMC), hybrid switches with different combinations of Si-IGBT, SiC-MOSFET, Si-FRD and SiC-SBD parallel or anti-parallel are comparatively investigated. By comparing losses MMC submodule (SM) bridge arm switching devices, one SM is replaced switch configuration, while other remains conventional Si-IGBT FRD configuration. I tot − E sw - V curves obtained for four configurations through SIMETRIX, brought to SIMULINK simulation...