The significant advance of power electronics in today’s market is calling for high-performance power conversion systems and MEMS devices that can operate reliably in harsh environments, such as high working temperature. Silicon-carbide (SiC) power electronic devices are featured by the high junction temperature, low power losses, and excellent thermal stability, and thus are attractive to converters and MEMS devices applied in a high-temperature environment. This paper conducts an overview of high-temperature power electronics, with a focus on high-temperature converters and MEMS devices. The critical components, namely SiC power devices and modules, gate drives, and passive components, are introduced and comparatively analyzed regarding composition material, physical structure, and packaging technology. Then, the research and development directions of SiC-based high-temperature converters in the fields of motor drives, rectifier units, DC–DC converters are discussed, as well as MEMS devices. Finally, the existing technical challenges facing high-temperature power electronics are identified, including gate drives, current measurement, parameters matching between each component, and packaging technology.

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Zr doping maintains the visible light absorption of LaTaON2 and contributes to enhanced photocatalytic activities for water splitting.

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A microrobot with untethered control in 3D space is a good choice to be applied in the fields of biomedicine with in small and confined workspace. In this paper, an electromagnetic actuation system (EMA) which combined with Helmholtz coil and Maxwell coil for the microrobot 5 DOF locomotion in 3D space is built. The magnetic field analysis of the proposed 3D EMA system was analyzed by finiteelement-method (FEM) with multi-physics COMSOL software. The proposed EMA system can produce magnetic field with different characteristics such as a controllable uniform gradient magnetic field, a rotating magnetic field and a oscillating magnetic field in a three-dimensional space by independently changing the current in each coil. In this paper the 3D motion dynamic equation model of microrobot was established. A novel control method for the gravity compensation for the wireless locomotive microrobot was proposed. The proposed method has the property that the direction of magnetic flux and the locomotion path of the microrobot are independent. Meanwhile, it can achieve the horizontal motions or nearly horizontal motions and overcome the gravity well at the same time. It has been verified by experiments in 3D liquid environment. With the proposed method, the microrobot shows good performance in horizontal motions as well as various motions in the 3D space.

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There is an unavoidable tradeoff between the control performance and the quality of service in networked control systems with resource constraints. To address the impact of network resources availability on requirement of bandwidth (RoB) and quality of control (QoC), an intelligent control approach to dynamic bandwidth management, namely fuzzy bandwidth management, is proposed based on fuzzy logic control technique. In order to guarantee the system's stability, the lower and upper bound of the assignable bandwidth are evaluated in terms of linear matrix inequalities and the resource constraints, respectively. In addition, the normalizable criterions of QoC and RoB are also defined, which can estimate the performance of the whole networked control systems. Preliminary simulations are carried out to highlight the merits of the proposed approach. It is argued that the proposed approach can save significant bandwidth and simultaneously improve overall control performance in comparison with the fixed bandwidth allocation and optimal bandwidth allocation.Keywords: Fuzzy bandwidth management, networked control systems, quality of control, requirement of bandwidth.