Parameter optimization method based on Pareto optimality under dual-mode configuration multi-target condition

Abstract

The invention relates to a parameter optimization method based on Pareto optimality under a dual-mode configuration multi-target condition, and belongs to the field of new energy vehicles. The method comprises the following steps: S1, constructing a steady-state kinetic equation under different configuration modes of a dual-mode configuration and a mode switching strategy based on transmission efficiency maximization; S2, establishing a hybrid power transmission system transient kinetic equation considering the rotational inertia of components; S3, based on a dynamic programming algorithm, constructing economic evaluation indexes including working condition related economic cost and transmission system part cost and a dynamic property evaluation index quantified by hundred kilometers of acceleration time; and S4, constructing a multi-objective optimization function through a Chebyshev aggregation method, and obtaining the economic cost related to the dual-mode configuration related working condition, the power transmission system part cost and the optimal Pareto leading edge of the dynamic property taking the acceleration performance as an evaluation index based on a multi-objective evolutionary algorithm MOEA / D. According to the method, a wider design space is provided for configuration optimization.

Description

technical field [0001] The invention belongs to the field of new energy vehicles and relates to a parameter optimization method based on Pareto optimality under the condition of dual-mode configuration and multi-objective. Background technique [0002] Vehicle hybridization is considered to be one of the most practical solutions to improve vehicle fuel economy at present. Among the various configuration designs of hybrid electric vehicles, the power split configuration is the most promising solution in the current market. According to different power split points, it can be further divided into input type power split, output type power split and composite power split. Due to the flexible speed ratio relationship and the existence of multiple degrees of freedom, the planetary gear train is usually used as a power split device in the transmission system of a hybrid electric vehicle. It can split the engine power into an electrical path and a mechanical path to drive the vehicl...

AI Technical Summary

Problems solved by technology

However, the nonlinear coupling of multiple performance objectives including configuration economy and dynamics complicates the optimal design of the power-split HEV powertrain

[0003] For multi-objective optimization problems, multiple conflicting objectives are usually combined in a specific weighted manner to form a single objective function for the subsequent optimization process. The optimality of the optimization objective mainly depends on the selection of the weight vector. When the design requirements occur When changed, the design process needs to be restarted, which significantly increases the uncertainty of the design process

In addition, when the Pareto boundary is non-convex, it is difficult for traditional weight-based methods to find the optimal solution

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