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Ling W.,Shanghai JiaoTong University | Liu D.,Shanghai JiaoTong University | Chen X.,Shanghai Municipal Electric Power Company | Liu J.,East China Electric Power Test and Research Institute Co. | He W.,Shanghai Municipal Electric Power Company
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2012

The feeder automation algorithm has the typical characteristics of discrete-type software. The reliability question has all along been one of the key restraining factors for large-scale application, being affected by various kinds of interference factors, including communication failures between system and site terminal unit, switch equipment refusing action, feeders changing its operation mode, and so on. This paper presents a failure-free evaluation test method for feeder fault location, isolation and restoration (FLISR) algorithm of reliability, and combines with Bayes identification test frequency selection method to determine test sample space. By averaging the test sample results on the user side of the contribution degree, the algorithmic reliability of quantitative score is obtained. Finally, an actual site of intelligence distributed feeder automation system is taken as an example for test, which verifies the effectiveness of the proposed reliability evaluation method. © 2012 State Grid Electric Power Research Institute Press. Source

Wang D.,NR Electrical Co. | Zhou Q.,NR Electrical Co. | Ding F.,NR Electrical Co. | Deng J.,NR Electrical Co. | Yang Z.,East China Electric Power Test and Research Institute Co.
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2014

The phase shifter as an efficient measure of regulating the power flow by inserting compensation voltage has important significance for improving the utilization ratio of transmission lines, balancing system power flow, and etc. Based on the thyristor controlled double core symmetry phase shifter, a simple system model is built in the real time digital simulator (RTDS) and the control device is developed. In consideration of the influence of different firing angles, a control strategy is proposed. The firing pulse is advanced before current zero-crossing when the voltage tap is fixed and after current zero-crossing when the voltage tap is being regulated. And a detection method of current zero-crossing is also presented. The result shows that the system is stable and harmonic-free at the fixed voltage tap. The transition is smooth and short-current-free during voltage tap regulation. Source

Lu Y.,Wuhan University | Lu Y.,State Grid Electric Power Research Institute of China | Qi X.-M.,East China Electric Power Test and Research Institute Co. | Zhang G.-Z.,Wuhan University | And 4 more authors.
Gaodianya Jishu/High Voltage Engineering | Year: 2010

The audible noise of DC transmission lines is different from that of AC transmission line and has no extruding component but a wide band. Therefore, studying the characteristics of the audible noise from the transmission line is very important for the prediction of audible noise of successor power transmission project. We measured the audible noise near the DC transmission lines that have the same voltage and different section. The frequency spectra of the audible noise of the DC transmission line were provided. The influence of other nature phenomena on the frequency spectrum of audible noise was analyzed. The results show that: audible noise from conductor of different section differs greatly; audible noise from ±500 kV DC operating lines is less than the limit of area of class 0(for example, villa, health resort); the wind noise will impact the low frequency part of the spectrum; the insect's singing in the daytime will impact the high level of the spectrum. Source

Qian Z.-Y.,East China Grid Company | Qian Z.-Y.,Xian Jiaotong University | Xiao R.,East China Electric Power Test and Research Institute Co.
Gaodianya Jishu/High Voltage Engineering | Year: 2010

In this paper, the artificial pollution cycle test equipment was established. Nature conditions (pollution quantity, wind, rain, fog) which influence the pollution degree of the transmission line insulators were simulated artificially. The test conditions of artificial pollution cycle testing were confirmed on the base of analyzing climatic characteristics in East China and the artificial pollution cycle testing were performed on the insulators which frequently are used in East China, meanwhile long term pollution accumulated characteristics of these insulators were obtained. By comparison with the test data from nature pollution accumulated on online insulators, the equivalence of artificial pollution cycle testing was demonstrated. Source

Zhang B.,Shanghai JiaoTong University | Zhang Y.,Shanghai JiaoTong University | Li L.,Shanghai Municipal Electric Power Company | Chi F.,East China Electric Power Test and Research Institute Co.
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2012

The reliability assessment based on connection point analysis is proposed to more comprehensively estimate the reliability level of transmission system. The definition of connection point and its identification, as well as the assessment index system of transmission system and its calculation formulas, are introduced. It collects the outage information of connection points in the system and calculates the related statistical indices to reflect the power supply capability transmission system. The momentary outage is considered and the trend of reliability change is reflected by the tendency index. Its effectiveness and practicability are verified by case study, which shows the influence of system structure on system reliability in the comparison of reliability condition between different transmission systems. Source

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