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.

The theoretical calculation method with formulae and the conventional measurement method of zero-sequence self-and mutual Mmpedance of high voltage cable lines are reviewed. Then the principles and mathematical models of zero-sequence parameter live-line measurement method of cable lines with mutual inductance based on GPS (Global Positioning System) technology are presented together with key techniques, hardware structure and software algorithm of the measurement system. Finally, field measurement results with the three different methods are given. Theoretical analysis and field measurement results prove that this new live-line method proposed in the paper is correct, effective and efficient.

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.

In this paper, a Power Line Carrier (PLC) communication system using a type of coded rthogonal frequency division multiplexing (COFDM) modulation is presented. Some application problems of the COFDM system are discussed. Key scheme of RSiTCM concatenated coding can correct errors. The performance of the proposed system with parameters is investigated through computer simulation. A good hit error rate(BER) result is observed.

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。