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This paper examines a new method on static tension measurement of overhead transmission line based on vibration spectrum analysis. Firstly, the causes of vibration of overhead transmission line are discussed. And then, static and dynamic characteristics of conductors are analyzed, and with reasonable simplification, taught string model is brought in to describe the relationships between static tension of overhead transmission line and its vibration spectrum. As following, a vibration and tension measurement system is set up to obtain vibration signal and tension data synchronously to verify the model. Finally, measurements on experimental transmission line are taken and experimental data are well analyzed. Results show that this model provides a good forecast on static tension of overhead transmission line and vibration spectrum analysis method is suitable for online monitoring and gives an effective alternative for traditional methods. [ABSTRACT FROM PUBLISHER]

A series of cross section data of electron interactions with SF6 has been used to calculate the positive point corona streamer in SF6 by using CMP. The calculated external current during single discharge ion has been divided into three stages of development to reveal the formation and propagation of streamer through the relationships of time and position of detailed electron and ion densities and electric field by simulation. In addition, 1-D and 2-D distribution of some detailed transient and intermediate products during corona are obtained and discussed. [ABSTRACT FROM PUBLISHER]