A Method for Measuring the Zero Sequence Distributed Parameters of Quadruple-Circuit Non-Full-Line Parallel Transmission Lines

With the development of power systems, the transmission corridors are becoming narrower, and it is very common for quadruple-circuit lines to share a part of the corridor. There is no corresponding line distributed parameter measurement method. This paper proposes an accurate measurement method for the distribution parameters of quadruple-circuit non-full-line parallel lines, establishes a non-uniform transmission line model of quadruple-circuit non-full-line parallel lines, and obtains the transmission matrix of the quadruple-circuit lines completely through Laplace transform. In addition, the mathematical expressions between the line parameters and the voltages, currents of the heads and ends of the lines are obtained. The zero-sequence voltages and currents of the first end and last end of the quadruple-circuit non-full-line parallel lines are simultaneously measured under four independent measurement modes, and are substituted into the proposed calculation formulae to solve 24 zero-sequence distributed parameters. The accuracy of the proposed method is verified by PSCAD simulation software. Compared with the existing measurement methods, the simulation results show that the proposed method has higher measurement accuracy than the existing methods. © 2022, Electrical Technology Press Co. Ltd. All right reserved.