A comprehensive review on the methods used for fault detection, classification and location in transmission lines and distribution systems is presented in this study. Though the three topics are highly correlated, the authors try to discuss them separately, so that one may have a more logical and comprehensive understanding of the concepts without getting confused. Great significance is also attached to the feature extraction process, without which the majority of the methods may not be implemented properly. Fault detection techniques are discussed on the basis of feature extraction. After the overall concepts and general ideas are presented, representative works as well as new progress in the techniques are covered and discussed in detail. One may find the content of this study helpful as a detailed literature review or a practical technical guidance.

Many research works have proved that it is viable to predict the radio interference (RI) of high‐voltage alternating current transmission lines by corona cage test. However, it is uncertain whether the same method can be adopted for RI prediction of high‐voltage direct current (HVDC) transmission lines, since the corona performance of HVDC lines is obviously affected by the widely distributed space charge. In this study, the detailed corona current characteristics, such as the current pulse amplitude, rise time, half‐wave time, and repetition frequency are systematically studied by the reduced‐scale experiment and the relationship between the average corona current and the RI excitation current is confirmed. Furthermore, based on the experimental study, a method for predicting the RI level of HVDC transmission lines by the corona cage test is proposed. The RI level of a ±800 kV bipolar HVDC transmission line is predicted and compared with the measured result, which verifies the validity of the proposed method.

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Aiming at the problem of low efficiency of logistics loading and unloading tools at the present stage, in this paper, a container loading and unloading device with minimal container volume ratio is designed. The mechanical model of each part of the device is established, the local parameters of the device are designed by MATLAB software, and the device is simulated and verified by ANSYS software. The results show that the design of the device is reasonable. Under the working condition of ultimate load 577.98 kg, the telescopic arm is allowed to extend 1 m outward to the container, the range of transverse movement in the container is 1.55 m, and the range of longitudinal movement is 4.36 m, which meets the design requirements of rigidity and strength, and accounts for only 7.34% of the volume of the container, it can meet the requirement of on board.

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