Online Zero Sequence Parameter Identification Of High Voltage Transmission Line Based On PMU

Zero sequence parameters of transmission line are important parameters for power system analysis and calculation. But there are still some problems in the measurement of zero sequence parameters, which is lack of the periodic measurement, costing the human and financial resources and influencing the reliability of power supply. Along with the rapid development of synchronous phasor measurement unit (PMU), the research of on-line identification of transmission line based on PMU data has attracted wide attention. This thesis is devoted to the study of zero sequence parameters identification of high voltage transmission line based on PMU data.(1) The single line zero sequence lumped parameters π-type equivalent model is established based on PMU data, and the non full phase steady-state data, when single-phase transient fault occurred, after the transmission line single-phase tripping to reclosing are used to identify zero sequence parameters. The influence of three phase measurement deviation on zero sequence component and the effect of zero sequence component deviation on the parameter identification results are presented by the simulation.(2) An adaptive IGG robust least square method for the identification of zero sequence parameters is proposed. The results based on simulation data verify the algorithm’s anti noise and anti error performance. The results based on PMU data show that the algorithm has practical value.(3) An anti error identification scheme based on adaptive IGG robust least square method is proposed, which includes the zero sequence model selection of the same pole and double circuit lines in 4 different operating modes. The identification results based on the simulation data and the PMU data verify the applicability of the scheme. At the same time, the relative sensitivity of each parameter is analyzed.