In this article, the repetitive avalanche ruggedness of silicon carbide metal–oxide–semiconductor field-effect transistors (MOSFETs) with asymmetric trench (AT) and double (DT) structure is investigated experimentally. The different failure mechanisms, i.e., thermal-induced fatigue or field oxide breakdown for AT-MOSFET electric induced gate degradation DT-MOSFET, are verified by device decapsulation TCAD simulation. Different from transient in single-pulse test, under stress related to...

In this article, short-circuit capability prediction and failure mode of 1200-V-class SiC MOSFETs with a double asymmetric trench structure are proposed under single-pulse stress. A model is established to evaluate withstand time corresponding critical energy devices various dc bus voltages. This can provide quick predictive guidance even if there few test results, the predicted values consistent practical values. Furthermore, two modes investigated in test. For MOSFETs, gate damage at lower...

Due to superior properties of silicon carbide (SiC), the unipolar conduction mechanism metal-oxide-semiconductor-field-effect transistor (MOSFET), and structural feature, double trench SiC MOSFETs have great potential be one next-generation power switches. In this article, an avalanche safe operation area (SOA) is established, a new failure behavior 1200-V MOSFET revealed timely through unclamped inductive switching (UIS) test (300 K initial temperature). With comprehensive analyses...

In this paper a novel improved multi-objective genetic algorithm (R-NSGA-Ⅱ) is proposed to solve the problem of dual-robot arc welding path planning. We strive find low-cost, fast and more efficient solution for large complex components. Firstly, optimization model planning established by considering various variables constraints in actual process. Then, R-NSGA-Ⅱ introduces recombination mechanism replace mutation operation NSGA-Ⅱ; can increase diversity individuals populations, global...

This paper focuses on the train under-vehicle inspection robot equipped with 3D solid-state LiDAR and laser distance sensor. Dedicated Simultaneous Localization Mapping (SLAM) framework motion control algorithm are proposed for operating in hazardous environment of pit. The constrained working includes repetitive monotonous spatial features makes autonomous localization navigation task a challenging issue. SLAM has complete architecture that frontend odometry loop closure detection. method...

Mobile inspection robots operate in narrow industrial sites have large mass and size are usually not allowed to perform autonomous global path planning or obstacle avoidance. Instead, the precisely follow pre-planned paths stop wait when encountering obstacles. The common working mode of is at points on path, collect images point cloud data, sometimes need pass through enter cramped spaces. To ensure effect passing ability, accuracy following reaching target pose very important for motion...

In order to realize high-speed train bogie's fault intelligent identification by data driven method, this paper proposes a new diagnosis framework. The main idea of the framework is use features ensemble empirical mode decomposition entropy, reduce feature dimension Isometric Feature Mapping Manifold Learning, and identify faults using support vector machine. proposed method increases detection rate effectively. Experimental results verify that accuracy bogie failure.

In this paper a novel heuristic path planning algorithm based on cross-entropy optimization is proposed for substation inspection robots. We seek to provide low-cost, fast and effective solution such The problem modeled topology map of the substation, it turns out be non-convex yet requires real-time solution. A classification applied simplify task points reduce computational cost speed up planning. used derive shortest among simplified points. Then, resolution implemented resolve original...

This paper addresses frequency response feature extraction of analog filter circuits. An approach for selection using criteria maximum relevance minimum redundancy (MRMR) and support vector machine (SVM) is proposed. Key idea the method to obtain candidate subsets with descending order MRMR first, then select optimal subset through cross validation results each SVM. Experimental testify that proposed has advantages less time-consuming selected features have reasonable distribution.

This paper presents a relocalization method which provides functions of odometry cumulative error correction, vehicle stopping position difference detection and localization algorithm system correction for the under-vehicle inspection robot equipped with 3D solid-state LiDAR. is based on novel point cloud uniaxial registration algorithm. The proposed utilizes grid occupancy to construct an efficient similarity measure function uses translation space search avoid falling into local optimum,...

In this paper a novel fuzzy controller based on self-adjusted parameter was proposed in the control of brushless DC motor (BLDCM). The principal and algorithm controlled analyzed. Speed current closed loop are involved controller. as outer works with help algorithm, while microcontroller optimizes parameters algorithm; inner obtain acceleration fast possible. experimental testing matched that simulation result. Fast response speed well good robustness proved by practical application.

This paper is concerned with sliding-mode boundary control (SMBC) of a vibrating string system under parameter variation. The excited by time-varying distributed disturbance. Dynamics the are described two types differential equations, namely: (a) non-homogenous hyperbolic partial equation (PDE) and (b) ordinary equations (ODEs). In proposed scheme, perturbations damped in presence law based on original infinite dimensional model applied at free end string. Robustness this scheme validated...

In this paper, the dynamics solution problem and boundary control for Timoshenko beam under uncertainties exogenous disturbances are addressed. The of represented by one non-homogenous hyperbolic partial differential equation (PDE), homogenous PDE, three ordinary equations (ODEs). authors suggest a method lines (MOL) obtaining in form ODE formula instead PDE formula. A global sliding mode (GSMBC) is designed vibration reduction influenced uncertainties, distributed disturbance, displacement...

Bogies support high-speed train carriage, stabilize trains on both straight and curved track improve ride quality by absorbing vibration they play a vital role in the operation of trains. This paper addresses faults diagnosis bogies using singular spectrum analysis. A modified difference criterion is formulated to select dimension subspace l, useful signal an original reconstructed l-dimensional subspace. detection statistic sum squared Euclidean distances between lag vector test matrix base...

In this paper a novel path planning algorithm based on improved ant colony optimization is proposed for dual-robot cooperative welding. We seek to provide low-cost, fast and effective solution such problems. The model of collaborative welding established actual process constraints shortest target. Then, dynamic transfer strategy information update are improve the (ACO+) model. Finally, ACO+ implemented solve problem in task large complex component. simulation demonstrates that method has...

By integrating H∞ control into iterative learning boundary (ILBC) with the method of lines (MOL), this paper suggests a novel scheme to reduce vibrations uncertain vibrating string system in presence iteration-varying distributed/boundary disturbances. The dynamics are defined by two kinds differential equations, namely: (a) non-homogenous hyperbolic partial equation (PDE) and (b) ordinary equations (ODEs). Firstly, MOL is employed attain form state-space instead PDE system. Secondly, ILBC...

In the presence of external disturbance, unmodeled dynamics and thrust saturation, this paper handles spacecraft relative position tracking problem for non-cooperative target by using line-of-sight (LOS) motion dynamics. By employing anti-windup technique nonsingular fast terminal sliding mode (NFTSM), adaptive control law is proposed to guarantee ultimate boundedness error state without prior knowledge upper bound disturbance system uncertainty. Finally, numerical simulation conducted...

In order to provide a low-cost, fast and effective solution for dual-robot cooperative welding problem, novel task planning method based on improved non-dominated sorting genetic algorithm II (INSGA-II) is proposed. The optimization model of collaborative established considering actual process constraints dual objectives the shortest no-load path minimum working time. Then, three chromosomes coding strategy adjustment operator are introduced improve (NSGA-II). Finally, INSGA-II implemented...