An impedance online inversion method for a power distribution line, comprising: on the basis of a section to be measured, selecting a measurement node of a main line and a measurement node of a
branch line (S1, S2); a main line
voltage square matrix, a main
line current column vector, and a main line
admittance column vector forming a main line
voltage matrix equation used for inversion calculation of main line
admittance, and further determining the
admittance of a main line section to be measured (S3, S4, S5, S6, S7); a
branch line
voltage square matrix, a
branch line current column vector, and a
branch line admittance column vector forming a
branch line voltage matrix equation used for inversion calculation of admittance of the
branch line, and further determining admittance of all branch line sections to be measured (S8, S9, S10, S11, S12); and determining the line impedance of all the sections to be measured by combining the admittance of all the main line sections to be measured and the admittance of all the branch line sections to be measured (S13). In the impedance online inversion method, accurate line impedance can be calculated and inverted online and in real time, and accurate line parameters and
topological information can be provided for real-time setting of a
power grid protection constant value and real-time
power flow calculations. In addition, applications such as
power grid planning, scheduling, operation control, source network load storage interaction, and the like, are supported.