Velocity Profile-Based Evaluation and Improvement of Lifetime of Power Devices in Railway Propulsion Inverters

In the work reported in this paper, the converter-level lifetime evaluation of power devices in a railway propulsion inverter is performed to assess and compare operating strategies of a railway vehicle in terms of reliability. Two groups of velocity profiles are considered for the lifetime evaluation, wherein all the velocity profiles have the same running distance and time. The first group consists of three operation velocity profiles with the same acceleration at starting and stopping, but with different cruising ranges. In the second group, three operation velocity profiles with different coasting times and acceleration values are considered. A strategy to improve the lifetimes of power devices in propulsion inverters is proposed for vehicles on a busy railway line.