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Publications (4)0 Total impact

  • Fan Chunju, Du Xiuhua, Li Shengfang, Yu Weiyong
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    ABSTRACT: A new adaptive fault location technique based on Phasor Measurement Unit (PMU) for transmission line is presented in this paper. Voltage and current phasors of both terminals of the transmission line are obtained through PMU. The online parameter-calculation algorithm is adopted to obtain the practical operating parameters when fault occurs, solving the problems that parameters provided by electric power company is different from the practical parameters because of the running environment and the operation history. The suddenly changed voltage and current are utilized to obtain suddenly changed positive voltage and current components to solve the system's impedance at the fault time. The on-line calculated system's impedance and parameters of the line are employed in the fault location equation and the fault location accuracy is high. The proposed fault location method is applied in single transmission line, parallel transmission line as well as teed transmission line. Extensive EMTP simulations as well as practical system data testing results have shown that the proposed technique accurately locate the fault point adaptively, not influenced by factors such as operation mode, fault resistance at fault point, fault type, prefault load and fault distance.
    Power Engineering Society General Meeting, 2007. IEEE; 07/2007
  • Li Shengfang, Hou Xingzhe
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    ABSTRACT: At the present time, substation equipments are inspected one by one by electric power workers in our country. It not only costs much manpower and material resources, but is also inefficient and insecure. The laser guided AGV based robot system used in substation inspection is a much better choice to solve the above problems. AGV, namely automatic guided vehicle, is a kind of simple mobile robot, which integrates sound, light, electricity and computer. And it is applied in the fields of industry manufacture and logistics widely and maturely. Improving the laser guided AGV in configuration, location, run and control software and so on combined with the requirement of substation operating standard, and then the improved AGV can be used in automatic inspection of substation equipments. The paper introduces the theory and application of laser guided AGV briefly, analyses the feasibility of improving AGV to meet the requirements of field environment and operation standard of substation, and then the design scheme of AGV based robot system used in substation equipment inspection is brought forward. The robot system can replace workers to inspect equipments in substation automatically or remote-controlled, and the operation automation of substation is improved to a new level. Accordingly, the application in substation inspection of the robot system based on laser guided AGV has notable economical benefits and social significance.
    Power System Technology, 2006. PowerCon 2006. International Conference on; 11/2006
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    ABSTRACT: A new adaptive fault location technique based on phasor measurement unit (PMU) for double circuit transmission lines is presented in this paper. Voltages and currents of the transmission line obtained through PMU are used for the on-line estimation of line parameters such as line impedance and capacitance. According to the fault feature of double circuit transmission lines a six-sequence fault component method is employed to implement fault location for parallel lines. For extremely long transmission lines, distributed capacitance has great influence on the accuracy of fault location. In the fault location method used in this paper, the distributed capacitance is allocated to the two terminals of the transmission line as lumped parameter in order to achieve higher accuracy. Extensive EMTP simulation results show that the proposed algorithm is independent of fault distance, fault type, fault resistance, uncertainty of transmission parameters and parallel line asymmetry.
    Developments in Power System Protection, 2004. Eighth IEE International Conference on; 05/2004
  • Fan Chunju, Li Shengfang, Yu Weiyong, K.K. Li
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    ABSTRACT: An adaptive setting scheme for distance protection relay based on phasor measurement unit (PMU) is proposed in this paper. Impedance of the transmission line is calculated to implement on-line setting of first zone distance protection. The voltages and currents of the two terminals of the transmission line and the current of the next transmission line from PMU can be used to obtain the synthetical system impedance that is used to obtain branch coefficient to implement online setting of second zone protection. Co-ordinated setting of distance protective relays can be carried out by the proposed method. Extensive EMTP simulation results have indicated that the equivalent operation mode of power system and the branching factor of protection can be obtained, and the on-line setting scheme can further raise the sensitivity of protection as well as insuring the selectivity and reliability of protection.
    Developments in Power System Protection, 2004. Eighth IEE International Conference on; 05/2004