Reliability analysis of large-scale electric bus depots based on different failure scenarios

Abstract

In order to decrease the harmful emissions of diesel buses, the senate of Hamburg has decided to allow buying only emission free buses by 2020. The two transportation companies in Hamburg; the Hamburger HOCHBAHN AG and Verkehrsbetriebe Hamburg-Holstein GmbH (VHH) are therefore converting their diesel bus depots to electric ones. Total of eight electrical bus depots are planned to be built during the upcoming years in Hamburg. Those bus depots should be able to serve approximately a total of 1500 buses by 2030. The transportation field is critical for every city due its daily usage. This paper analyzes the cases of having different failure scenarios in the components of the charging infrastructure and their effect on the charging processes of the buses. Additionally the contribution of this paper is to show the effects of the failure scenarios on the routes assigned to the concerned buses. In one of the bus depots, a second-life battery is implemented to the system. In the other bus depot, a 5 MW emergency connection is simulated. Both have the target of decreasing the severity of the situation. For this purpose many charging scenarios are considered to simulate these effects at diverse operational conditions. As a conclusion, the degree of severity of each case is presented based on the failures consequences.