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This paper proposes a design scheme for a wireless power transfer (WPT) system based on multi-relay coils to solve the power supply demand of 500 kV transmission line online monitoring equipment. The relationship between the operating frequency and the coil loss is established to analyze the influence of the number of relay coils and the coil distance on the transmission performance. The particle swarm optimization model is established with transmission efficiency as the optimization objective. The distribution spacing between coils, the working frequency, and the number of coils are optimized. Based on the equidistant arrangement of relay coils, an optimization scheme of non-equidistant arrangement is proposed. Under the condition of the same number of relay coils, the transmission efficiency of the system is increased by 20.56% and has been verified by experiments. In addition, finite element analysis software has simulated the surrounding high-voltage field strength of the WPT system added to the insulators. The results show that the insulators still meet the insulation standards. The simulation and experimental results show that the proposed scheme can effectively meet the power demand of high-voltage line monitoring equipment. [ABSTRACT FROM AUTHOR]

"Through space" metal/hydrogen shift constitutes one of the efficient elementary step in organometallic chemistry to achieve selective remote C−H bond functionalization. Compared with the relatively extensive exploration on 1,4‐palladium migration, the processes on corresponding 1,5‐palladium translocation are far less explored. Based on our understanding on related research areas, we summarized the advances achieved in remote C−H bond activation through a key step of 1,5‐palladium migration in this minireview. The background, reaction scope, and more importantly, the mechanistic rationale of each transformation was discussed. We hope by reading through this minireview, one could get a general perspective on direct C−H bond activation via 1,5‐palladium/hydrogen shift, and could understand why such a process is less common when compared with the process going through 1,4‐palladium/hydrogen migration, and eventually could be inspired to develop practical ways for the synthesis of valuable molecules, which could not be prepared easily through other traditional approaches. [ABSTRACT FROM AUTHOR]

To fully utilize the voltage regulation capacity and interaction characteristics of the Transmission and Distribution (T&D) system, a novel Modified Partially Observed Markov Decision Process (MPOMDP)‐based Reinforcement Learning (RL) scheme for Autonomous Voltage Control is proposed, which incorporates Demand Response (DR) and cooperation with the Transmission Network. The proposed scheme consists of two vital components: an MPOMDP block and a Modified Asynchronous Advantage Actor‐Critic‐based RL block. The MPOMDP block innovatively exploits the confidence interval of the observed state to make a better perception of the precise system state by introducing two new probability vectors. Then the MPOMDP block is fed into the underlying architecture of the RL block for asynchronously capturing features and optimal decision‐making, where the solving framework additionally brings in a public data buffer to realize boundary information sharing. Case studies are conducted on a modified T&D system considering N‐1 contingencies, with a training dataset from a district in Suzhou, China. Simulation results demonstrate that the proposed scheme can achieve significant voltage optimization while ensuring fast convergence speed. [ABSTRACT FROM AUTHOR]

The energy harvesting of ultra‐high voltage transmission lines and wireless power transmission technology are effective means to solve the stable energy supply of outdoor tower equipment. However, there are inevitably technical problems such as long transmission distance, weak coupling, and parameter sensitivity. In this paper, an effective design approach for a power demand‐oriented long‐distance wireless power transmission system is proposed. With the goal of transmitting power, a system equivalent parameter model is established to address the sensitivity of design parameters for the point‐to‐point long‐distance wireless power transmission system, and the main influencing factors that lead to system power transmission failure are analyzed. To effectively address the impact of high‐sensitivity parameters, a fast‐tuning method with redundant capacitance matrix compensation is proposed, which improves the deviation problem in system parameter design, improves the efficiency of offset parameter matching, and analyzes the impact of wireless energy transmission systems on high‐voltage insulator strings. Finally, an experimental platform was constructed to achieve power transmission at a distance of not less than 5 m at a resonant frequency of 50 kHz. The transmission efficiency met the design expectations and verified the effectiveness of the analysis. [ABSTRACT FROM AUTHOR]

This article develops a prediction and path planning system based on the graph neural network to navigate a robot in a complex dynamic environment. In particular, the core of this method is to predict those aspects of the future that are directly relevant for planning, including their value, state, and policy. A graph neural network-based method is introduced to encode the interaction between the robot and the surrounding environment. Then, the dynamic model of the environment is learned through the model-based reinforcement learning, and the path is planned using the Monte Carlo tree search method according to the learned model. Finally, simulation studies are given to evaluate the validity and advantage of the obtained algorithm compared with the most recent methods. It has been shown that the proposed method achieves a higher success rate within a less time. Meantime, the oscillatory and freezing problems caused by the short-sightedness of the robot are avoided. [ABSTRACT FROM AUTHOR]