Nonlinear Dynamic Structural Optimization of Electric Vehicles Considering Multiple Safety Tests

Abstract

A nonlinear dynamic structural optimization method is presented for the design of electric vehicles. A pack crush test and a pole impact test are selected as two different types of battery pack safety assessment. Two finite element models are defined for the pack crush test and the pole impact test, and two optimization problems are formulated for each test, respectively. The battery pack is the shared part of the two finite element models. The equivalent static loads method is employed for the nonlinear dynamic response optimization of the multi-model. The current equivalent static loads method can consider only one model while the current multi-model optimization is only for linear response optimization. A novel equivalent static loads method is proposed to handle multiple finite element models by using multi-model optimization. The mass of the structure is minimized, and displacement constraints are defined on the intrusion of the battery pack to prevent fire in the analyses. The resultant design can protect the battery system from physical shocks and car accidents.