基于键合图的物理模型降阶方法

Bond-graph-based physical model order reduction method

基于动态系统物理表达方法——键合图法,给出了物理模型降阶方法——模型降阶算法(MORA),对流经组件的功率流进行比较,以确定元件的活跃性及相对活跃性,据此对模型进行简化,并对MORA方法进行了改进,同时给出了低活跃性元件去除的物理解释.最后,对汽车的键合图模型进行了降阶,仿真结果证明,降阶后模型的动态特性与原模型动态特性高度吻合,证明基于物理的模型降阶算法是非常有效的.

The order reduction methods aim at simplifying physical model while retaining physical components or subsystems with regard to system dynamic behaviors. In this study, a physical model reduction algorithm （MORA） is proposed based on a physical representation of dynamic systems, i.e. the bond graph method. In comparison of component power flows, the model order is reduced through identifying the dynamic and subdynamic components. Afterwards, the MORA is further enhanced by interpreting the elimination of lowdynamic elements. Finally, a case study on automobiles＇ bond graph is used to illustrate the MORA. From simulation results, it is indicated that the dynamic properties of order-reduced model coincide with those of original model. Therein, this approach has proven its effectiveness.