Research On Performance Testing And Quantitative Evaluation Method Of Electric Power Steering System

The electric power steering system relies on the assisting motor to provide the steering torque,and the electronic control unit controls the direction and size of the assist.It can well solve the contradiction between the lightness and road feeling that the traditional power steering system can not achieve,and has the advantages of energy saving,environmental protection,no leakage,etc.,making the electric power steering system become the current mainstream trend of automobile steering.With the increasing output of electric power steering products,the evaluation technology for its performance has become a hot topic of study today.Based on the background of the electric power steering system researched and developed by the research group,this paper sets up a test bench for the electric power steering system,analyzes two existing products and one self-developed product,and proposes an objective quantitatively comprehensive evaluation model.The main research content includes:1.Based on the test bench,a data acquisition system for performance testing of electric power steering systems was designed and developed,which is divided into hardware and software.The hardware part includes: sensor selection and signal conditioning circuit designed according to the characteristics of the sensor and acquisition card;the software part includes: data acquisition module,data storage module,data reading module,and data analysis module.2.According to the "Technical Requirements and Test Methods for Automotive Electric Power Steering Devices",performance tests were conducted on two commercially available products and the self-developed product.The results showed that the three electric power steering system products met the relevant standards in qualitative analysis.Quantitative evaluation of the three electric power steering systems,selecting five performance evaluation indicators,calculating the index of each individual item for each product in turn,and formulating a 1-5-point quantitative evaluation standard table for each product.Item evaluation draws scores to achieve objective quantitative performance evaluation.3.Analyze the performance evaluation model of the electric power steering system by using the analytic hierarchy process.Calculate the impact weights of the five evaluation indexes on the steering sensation respectively.Then multiply each of the five evaluation scores of each product by the weights and sum them to obtain the comprehensive evaluation score of the electric power steering system product,and verified the validity of this model through the subjective evaluation method.This paper proposes a comprehensive evaluation model of the electric power steering system.The advantage of this model is that it is sometimes difficult to judge through the subjective judgment of a person that the performance of a single index is close or that there is a large difference between various indexes.After this method is introduced,it is possible to directly and quantitatively calculate the comprehensive score of the products of the electric power steering system without relying on subjective feelings of human beings,so as to directly compare the merits and demerits of several products.The method proposed in this paper has certain significance for the evaluation of electric power steering system products.