Mechanical model of dynamic shock response calculation using modal superposition was analyzed, and based on this mechanical model, a dynamic shock simulation calculation was conducted for auxiliary converter cabinet on a certain vehicle by means of finite element method, which was checked with application of IEC 61373 standard. Besides, results of simulation calculation were verified by means of experimental test. Reliability of the structure and accuracy of the mechanical model were assured with above calculation and test, which provided theoretical basis for the simulation calculation’s application in product preliminary development period.