A Simulation Free Nonlinear Model Order Reduction Approach and Comparison Study

In this paper a new approach to the model order reduction of nonlinear systems is presented. This approach does not need simulation of the original system and therefore it is suitable for large systems. By separating linear and nonlinear parts of the original nonlinear model, the idea is considering the nonlinearity of the system as additional inputs. Based on this linear system, a known order reduction method can be applied to £nd the coef£cients of nonlinear parts and linear parts of the reduced order model. An approximation of the original states is constructed as a linear combination of the states and inputs of the reduced order system. For comparison to some known methods in order reduction of nonlinear systems, three other methods are discussed brie¤y. At the end, a technical nonlinear system is considered to be reduced and the results found from the different methods are compared.