The invention provides a method for measuring a strength index of interaction between converter stations of a multi-feed
direct current system. The method comprises the following steps that (1)a multi-feed
alternating current and
direct current power grid receiving
end system is taken as a research focus,
direct current converter stations to be researched are determined, and it is assumed that the number of the direct current converter stations to be researched is N, and the direct current converter stations to be researched have three phases of A, B and C; (2) electromechanical transient
simulation calculation is conducted on the
power grid with electromechanical transient
simulation software, a single-phase grounded
short circuit with certain resistance is arranged at the phase A at a converter
bus i, i=1, 2, ...N, the change of the
voltage of the phase A at the converter
bus i is observed, the grounded resistance of the
short circuit is adjusted constantly, the
voltage of the phase A at the converter
bus i drops by 1% after the
short circuit, the variation
delta UAj of the
voltage of the phase A at the converter bus j is recorded, j=1, 2, ..., i-1, i+1, ...N, and the calculation of the phase B and the calculation of the phase C are identical with that of the phase A; (3) a single-phase multi-feed
interaction factor SMIIFij between the converter
station i and the converter
station j is calculated. By means of the method, references are provided for evaluating the strength of the interaction between all converter stations in the multi-feed direct current
system in asymmetrical faults.