Study On Identification Of Powertrain Inertia Properties Based On Modal Model Method

Powertrain is one of the important vibration sources of automobile,which directly affects the NVH characteristics of automobile.Reasonable design of powertrain mounting system can restrain the transmission of vibration to the body,thus greatly reducing the vibration and noise of the whole vehicle,which is conducive to improving the ride comfort and prolonging the fatigue life of the vehicle.Inertial parameters(mass,center of mass,moment of inertia and product of inertia)of powertrain are the important premise and basis for optimum design of mounting system.Therefore,it is of great practical significance to study an accurate and efficient method for identifying inertial parameters of powertrain.In order to identify the inertia parameters of power assembly efficiently and accurately,this paper focuses on the inertia parameters identification method,principle identification device and experiment based on modal model method.Firstly,the inertial parameter identification algorithm based on modal model method(C-B method and T-N method)is studied in detail in theory,and the recognition algorithm program is compiled,and the correctness of the method is verified by an example.Then,the identification algorithm is directly applied to the identification of inertia parameters of powertrain assembly under the condition of vehicle installation.The identification results show that the minimum identification error is about 25%.It shows that the identification of inertia parameters of powertrain assembly under the condition of real vehicle installation can not meet the needs of practical engineering application.In order to improve the accuracy and efficiency of inertial parameter identification,an experimental device for inertial parameter identification of power assembly based on modal model method is designed.The correctness and effectiveness of the experimental device are verified by numerical simulation.By means of simulation analysis,the main influencing parameters(coordinate error of response point,condition number of matrix and mode shape)and their influencing rules are determined.Finally,a principle experimental device is built to calibrate the inertia parameters of the identification device with calibration blocks.Taking the standard block with known inertia parameters as the research object,the inertia parameters identification experiment based on modal model method is carried out.The recognition results show that the recognition errors of mass and centroid coordinates of standard blocks are within 10%,the recognition errors of moment of inertia and product of inertia are slightly larger,but the maximum error is controlled at about 24%.It shows that the recognition results are consistent,and the identification accuracy of inertia parameters of T-N method is higher than that of C-B method.The validity and reliability of the identification method and device are further verified.The identification method and device have certain practical engineering application value.