Various technologies have recently been developed for high-speed railways, in order to boost commercial speeds from 300 km.h： to 400 km.h-1. Among these technologies, this paper introduces the 400 km-h-1 class curren...Various technologies have recently been developed for high-speed railways, in order to boost commercial speeds from 300 km.h： to 400 km.h-1. Among these technologies, this paper introduces the 400 km-h-1 class current collection performance evaluation methods that have been developed and demonstrated by Korea. Specifically, this paper reports details of the video-based monitoring techniques that have been adopted to inspect the stability of overhead contact line （OCL） components at 400 km.h-1 without direct contact with any components of the power supply system. Unlike conventional OCL monitoring systems, which detect contact wire positions using either laser sensors or line cameras, the developed system measures parameters in the active state by video data. According to experimental results that were obtained at a field-test site established at a commercial line, it is claimed that the proposed mea- surement system is capable of effectively measuring OCL parameters.展开更多
Significant investments have been made regarding the construction of a great number of high-voltage overhead power lines of all voltage levels, and now the questions arise on where and how to direct the investments ne...Significant investments have been made regarding the construction of a great number of high-voltage overhead power lines of all voltage levels, and now the questions arise on where and how to direct the investments necessary for the maintenance of overhead power lines. To organise the process of maintenance of overhead power lines correctly, it is necessary to have the current information on the condition of particular components of a line. In this paper, special attention has been paid to the real condition of overhead power lines, with the aim of making the decision whether some of the following measures are necessary, and to what extent： the revitalisation for a certain number of years is perceived, the revitalisation up to five years and reconstruction of the overhead power line is performed, its restoration is performed or nothing is done. The approach to the perceiving of real condition of high-voltage overhead power lines is presented on a global block diagram. With the aim of setting out the list of priorities for revitalisation, the criteria have been defined with regards to the real condition of particular components of an overhead power line, as well as pursuant to the role and importance in an electric power system. The correctly defined criteria contribute to the solving of the problem of making a single list of priorities for the revitalisation of high-voltage overhead power lines. In that way, the recommendations are being given to the transmission companies, to achieve a higher reliability of an electric power system, with a minimum number of cancellations and a maximum extension of working life of all the components of overhead power lines. A correct maintenance of overhead power lines brings large financial savings to the owners of transmission companies, and that is the primary goal in a deregulated environment.展开更多
Based on the energy distribution and economy status In the Northwest Region in China, this paper analyzes the probability of power sources complementation between Northwest Power Grid and the adjacent regional power g...Based on the energy distribution and economy status In the Northwest Region in China, this paper analyzes the probability of power sources complementation between Northwest Power Grid and the adjacent regional power grids, and points out that the strategic emphases for Northwest power development are to speed up 750 kV transmis-sion system construction, expand the Regional power market, rolling-develop hydrdpower stations on the Upper Yellow River, speed up thermal power bases construction and boost the interconnection between Northwest and North China, etc.展开更多
文摘Various technologies have recently been developed for high-speed railways, in order to boost commercial speeds from 300 km.h： to 400 km.h-1. Among these technologies, this paper introduces the 400 km-h-1 class current collection performance evaluation methods that have been developed and demonstrated by Korea. Specifically, this paper reports details of the video-based monitoring techniques that have been adopted to inspect the stability of overhead contact line （OCL） components at 400 km.h-1 without direct contact with any components of the power supply system. Unlike conventional OCL monitoring systems, which detect contact wire positions using either laser sensors or line cameras, the developed system measures parameters in the active state by video data. According to experimental results that were obtained at a field-test site established at a commercial line, it is claimed that the proposed mea- surement system is capable of effectively measuring OCL parameters.
文摘Significant investments have been made regarding the construction of a great number of high-voltage overhead power lines of all voltage levels, and now the questions arise on where and how to direct the investments necessary for the maintenance of overhead power lines. To organise the process of maintenance of overhead power lines correctly, it is necessary to have the current information on the condition of particular components of a line. In this paper, special attention has been paid to the real condition of overhead power lines, with the aim of making the decision whether some of the following measures are necessary, and to what extent： the revitalisation for a certain number of years is perceived, the revitalisation up to five years and reconstruction of the overhead power line is performed, its restoration is performed or nothing is done. The approach to the perceiving of real condition of high-voltage overhead power lines is presented on a global block diagram. With the aim of setting out the list of priorities for revitalisation, the criteria have been defined with regards to the real condition of particular components of an overhead power line, as well as pursuant to the role and importance in an electric power system. The correctly defined criteria contribute to the solving of the problem of making a single list of priorities for the revitalisation of high-voltage overhead power lines. In that way, the recommendations are being given to the transmission companies, to achieve a higher reliability of an electric power system, with a minimum number of cancellations and a maximum extension of working life of all the components of overhead power lines. A correct maintenance of overhead power lines brings large financial savings to the owners of transmission companies, and that is the primary goal in a deregulated environment.
文摘Based on the energy distribution and economy status In the Northwest Region in China, this paper analyzes the probability of power sources complementation between Northwest Power Grid and the adjacent regional power grids, and points out that the strategic emphases for Northwest power development are to speed up 750 kV transmis-sion system construction, expand the Regional power market, rolling-develop hydrdpower stations on the Upper Yellow River, speed up thermal power bases construction and boost the interconnection between Northwest and North China, etc.
