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【期刊论文】The Effects of Flexible AC Transmission Systems Device on Protective Relay
张承学, Fan Dawei, Zhang Chengxue, Hu Zhijian, Wang Wei
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-1年11月30日
The paper introduces the basic structure and equivalent circuit model of Unified Power Flow Controller (UPFC) in the beginning, and then analyzes its effects on transmission line distance relay in two cases. Different location of the UPFC, the fault resistance, the parameters of UPFC, the location of fault and system operation conditions will all affect the measured apparent impedance to some degree. The presence of UPFC will make the relay under-reach or over-reach. In order to eliminate the effects of UPFC device on protective relay, two methods are given in this paper. One is to equip protective relay devices in which the UPFC device is equipped. In this way the UPFC device is always beyond the fault loop. The other is to use Artificial Neural Network to eliminate the effects of UPFC device.
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【期刊论文】Realization of High Speed Digital Carrier Communication Module Using COFDM
张承学, Yang Yu, Hu Zhijian, Zhang Chengxue, Zhou Qiang, Zhou Haibin
2004 IEEE International Conference on Electric Utility Deregulation, Restructuring and Power Technologies (DRPT2004) April 2004 Hong Kong,-0001,():
-1年11月30日
In this paper, realization of high speed carrier communication module using new coded orthogonal frequency division multiplexing(C0FDM) is discussed. OFDM theory and its coding technology are simply introduced. The advantage of using COFDM modulating technology in power carrier wave communication is analyzed, and data transfer flow of the corresponding COFDM wave-carrier system is presented. The module design based on DSP is put forward, Channel coding simulation and hardware composition and realization are also presented in this paper.
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35浏览
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张承学, 张景超, 吴方劼, 王鹏
电力系统自动化,2005,29(15):86~88,-0001,():
-1年11月30日
在现代电力系统广域保护和稳定控制系统中,同步相量测量单元(PMU)起着重要作用。目前应用于我国电网中的PMU大都是基于美国全球定位系统(GPS)提供的授时信号来实现同步数据采集的。从保障互联电网的安全出发,文中提出了基于我国“北斗一号"卫星定位系统来开发适合我国电网的PMU,并论证了该方案的可行性。
同步相量测量单元, 互联电网, 北斗卫星定位系统, GPS
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51浏览
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张承学, 王卉, 胡志坚, 彭晓莺, 陈楷
继电器,2004,32(18):13~16,-0001,():
-1年11月30日
光纤架空复合地线(OPGW)中故障电流的计算是其设计选型中的一项重要工作,针对OPGW工程计算中常遇见的两个问题所带来的计算误差:忽略经变压器中性点通过变压器线圈流向导线的电流及忽略导线系统与地线系统的互阻抗,提出一种基于EMTP软件的电磁暂态计算方法:该方法可以有效地解决上述问题,准确度较高。
光纤架空复合地线, 短路电流, 电磁暂态仿真程序, 电磁暂态计算
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37浏览
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张承学, 冯小华
高电压技术,2004,36(6):26~27,-0001,():
-1年11月30日
谐波分析法在线测量介损时易因频率波动产生泄漏误差,为此在非同步采样下推导出介损测量的完整时域表达式,提出先估算频率偏差再用它来修正原谐波分析法的改进方法。MATLAB 6.5对原谐波分析法和修正谐波分析法求介损因数的仿真结果表明,非同步采样下修正法的准确度显著提高,自适应调整采样频率时两周后介损测量最大绝对误差就已≯7.5×10,完全满足介损测量高准确度要求。
谐波分析法 修正 介损测量 非同步采样
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25浏览
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