The invention relates to a theven equivalent overall modeling method of a modularized multi-
level converter (MMC), belonging to the technical field of
power transmission and distribution. The electromagnetic transient off-line
simulation efficiency of the MMC is determined by the integral
computation complexity of a converter part and a modulation
voltage-sharing part of the MMC, and the two parts are respectively optimized in three levels by the overall modeling method of the MMC. The core technological scheme provided by the invention is as follows: firstly, assuming the equivalence to be an infinite
resistor (ROFF= infinity) when a switch element in a theven
equivalent model of the MMC; secondly, discretizing all submodule capacitors in the MMC by adopting a regressive
eulerian method, so as to replace a trapezoid
integral method in the known model; and finally, providing a novel sequencing and
voltage-sharing
algorithm by combining the infinite
resistor with a turn-off characteristic and the regressive
eulerian method, wherein the
computation complexity of the novel sequencing and
voltage-sharing
algorithm is the same as the number of the bridge arm submodules of the MMC. The complexity of the electromagnetic transient simulating calculation of the MMC can be linearly changed along with the increasing of the number of the submodules under the premise of guaranteeing the
simulation precision, so that the overall modeling method has important reference significance on researchers in the field of the MMC.