A New Method for Live Line Measurement of Zero Sequence Parameters of T-Type Transmission Lines with Mutual Inductance

A new method for live line measurement of zero-sequence parameters of T-type transmission lines with mutual inductance is proposed. Firstly the T-type lines and multi-branch lines are equivalent to parallel transmission lines with mutual inductance, and then the live line measurement for parameters of T-type transmission lines is achieved by using integral equation. Measuring principle of live line measurement, noise processing of data sampling and error correction and mathematical model of approximate calculation are explained in detail. This method uses global positioning system as the synchronous time tag of data acquisitions at different substations. The digital simulation results prove that the new method can meet the needs of live line measurement of inductance parameters.