Wang X.,Guangzhou Meteorological Bureau |
Chen S.,Guangdong Lightning Protection Center |
Zhang Y.,Chinese Academy of Meteorological Sciences |
Huang Z.,Guangdong Lightning Protection Center |
Cai L.,Wuhan High Voltage Research Institute
Dianwang Jishu/Power System Technology | Year: 2011
The experimental investigation on over-voltage protection for outdoor low-voltage overhead transmission lines is carried out. Based on a typical natural lightning with multi return strokes and combining with lightning location data, the values of over-voltages at entrance terminals for housings and those at front-side of collector, which locate at differnet positions of transmission lines and the residual voltage characteristics of surge protective devices (SPD) located at collector front-side as well as the relation between over-voltages of L-lines at entrance terminals for housings and return stroke current of lightning are analyzed and discussed. Analysis results show that close range lightning can lead to induced over-voltage with amplitude of several kilovolts on low-voltage overhead transmission lines and the duration of this over-voltage is about 1.0 ms in average; after the action of SPDs installed at the front-side of collector the over-voltage waveforms at farther entrance terminals for housings will be influenced, and the duration of residual voltage after the action of SPD is about 218 μs in average, which is longer than the duration from standard 8/20 μs test waveform; and there is good linear fitting relation between induced over-voltages at entrance terminals for housings and the ratio of return stroke currents to return stroke distances.
Wang L.,Wuhan High Voltage Research Institute |
Zhu J.,The Quartermaster Equipment Institute of the General Logistics
Advanced Materials Research | Year: 2013
A new aerobics intelligent motion capture system using MEMS is proposed based on analyzing key technology of recent human motion capture system which is most benefit forintelligent tutoring system. Architecture of aerobics intelligent motion capture system is designed. And core technology solutions of the system including large-scale aerobics tutoring and training motion data obtain system, multi-position micro-electro-mechanical sensors system based on wireless network and multi-source data fusion and processing system with high-frequency real-time data transmission system are put forward. © (2013) Trans Tech Publications, Switzerland.
Li P.,Huazhong University of Science and Technology |
Kang J.,China Electric Power Research Institute |
Ruan L.,China Electric Power Research Institute |
Xu X.-Y.,Huazhong University of Science and Technology |
And 3 more authors.
Journal of Electrostatics | Year: 2014
At present, there is no appropriate measurement techniques for space charge. In this paper, a U-shaped cavity device is developed as the space charge measurement device, which can be applied to transmission lines. Its design principle and calculation techniques of design parameter are also introduced. To test the space charge measurement accuracy of the U-shaped cavity device, a space charge generator is developed specifically for this experiment. The test results are excellent and show that the U-shaped cavity device can meet the design requirements. This technique is suitable for space charge measurement under transmission line normally charged work condition. © 2014 Elsevier B.V.
Lu F.-C.,North China Electrical Power University |
You S.-H.,North China Electrical Power University |
Liu Y.-P.,North China Electrical Power University |
Wan Q.-F.,Wuhan High Voltage Research Institute |
Zhao Z.-B.,North China Electrical Power University
IEEE Transactions on Power Delivery | Year: 2012
Corona loss generated from conductors is one of the important design factors of extremely high-voltage ultra-high voltage (EHV/UHV) ac transmission lines. The charge simulation method was adopted to calculate conductor corona loss in the corona cage. Every corona cage wall is equivalent to the ground plane and, therefore, the calculation model is more complicated than the power-line model above the ground surface. Two corona cagesUHV corona cage and small corona cagewere adopted in the tests. The cages are both square sections. Single conductors and bundle conductors were tested in the corona cages to verify the corona cage calculation model. And the same type of conductor was tested in the small corona cage and in the UHV corona cage to check the measuring system and the simulation program of corona loss further. Since the artificial rain rates were from 12 to 20 mm/h, corona losses were measured and calculated. The results indicate that the fundamental frequency component is the most main component of corona loss. The corona cage corona-loss calculation model is appropriate. And for single conductor LGJ-500/35 and bundle conductors, 8 × LGJ-500/35, under heavy rain conditions, with the rain rate being from 12 to 20 mm/h, the roughness coefficient m range is from 0.4 to 0.5 approximately. © 2012 IEEE.
Hu J.-X.,Wuhan High Voltage Research Institute |
Liu K.,Wuhan High Voltage Research Institute |
Liu T.,Wuhan High Voltage Research Institute |
Xiao B.,Wuhan High Voltage Research Institute |
Wu T.,Wuhan University
Gaoya Dianqi/High Voltage Apparatus | Year: 2010
With the implement of 'power transmission from west to east' project and the application of compact transmission technology, many compact transmission lines have been applied in China, even in high altitude areas of China. In order to carry out living work on these lines, it is necessary to study the approach distance and complex gap during living work. A serial experiments have been carried out to research the living work of 500 kV compact transmission lines in high altitude area. The risk rate of approach distance and complex gap of living work on compact transmission line at altitude between 2000 m and 3000 m are calculated according test results. The results of calculation show that approach distance and complex gap of Dehong compact high-altitude 500 kV transmission line satisfy the safety requirement of living work. Research results provide references for the design of pole and tower and impeletion of living work of 500 kV compact transmission lines in high altitude area.