The invention relates to a method for calculating rotor dynamics performance of a multi-parallel-
axis system. The method comprises the steps specifically as follows: step (1), selecting an analysis object and a calculation type, inputting parameters of a bearing-rotor
system, finishing pre-
processing operations like
discretization of the rotor
system; step (2), calling a bearing calculation program, calculating dynamic and static characteristic parameters of each bearing, forming a rotor dynamics equation of a parallel
axis system which gives consideration to gear engagement according to the selected analysis object and calculation type; and step (3), calling a solving function to calculate a feature value and a
feature vector of a dynamics
differential equation, converting the feature value and the
feature vector into dynamics characteristic result data through dimension so as to finish calculation and analysis of
system stability, critical rotation speed, forced
vibration response and vibration mode. According to the method disclosed by the invention, calculation and analysis means for dynamics performance of the multi-parallel-
axis system, which can be applied to actual
engineering, are developed on the basis of
solid theoretical research; the calculated rotor system comprises supports of various types; therefore, combination of bearing calculation and rotor
system dynamics analysis is implemented better.