Objective The mass characteristic parameters of the on-board equipment are key elements for the quality evaluation of urban rail transit vehicles, directly affecting the overall performance and running safety of the train. As a core component of urban rain transit vehicle’s electrical traction drive system, the converter is characterized by large volume, complex structure, and specialized installation methods. Therefore, traditional mass characteristics measurement methods are no longer applicable, necessitating research on new measurement methods.

Method Referring to QJ 2258A—2001, a mature technical standard for spacecraft mass characteristic testing, an undercarriage equipment converter of urban rail transit vehicle in a Chinese city is taken as the test specimen, the tooling is designed according to the structure of the converter. Using integrated testing equipment, the attitude of the converter is adjusted via a 3-axis coordinate transformation device, and the corresponding mass characteristic parameters are obtained by the method of taking the arithmetic mean of multiple measurements. To ensure reliability, finite element modeling and static stress analysis are performed on the tooling before testing, and the measured values are compared with the calculated values.

Result & Conclusion  The designed tooling for the converter can meet the static strength requirements; the measured values of the converter's CoM (center of mass) and rotational inertia parameters are very close to the calculated values, with a maximum deviation between the two being only 2.5%. Therefore, the proposed testing method is feasible and effective.