Experimental Analysis of a Zebra Battery Based Propulsion System for Urban Bus under Dynamic Conditions

Abstract In this paper preliminary results on a Zebra battery based propulsion system for urban bus applications are presented. The analysis is carried out with the support of a laboratory 1:1 scale test bench, focusing the attention on a 65 kW electric drive, specifically designed for urban bus applications, supplied by two 20 kWh Zebra batteries working in parallel. The electric power train is connected, through a fixed ratio gear box, to a 100 kW regenerative electric brake provided with speed and torque controls, in order to evaluate the propulsion system performance in steady state and dynamic operative conditions. On the base of the architecture of a urban bus, powered by the same electric propulsion system studied in laboratory, a Matlab-Simulink model has been carried out to assess the dynamic behavior of the full electric urban bus and also other possible hybrid configurations, working on standard and real driving cycles, taking into account the resistant forces represented by proper vehicle/road/aerodynamic parameters. For the above configurations an evaluation of the expected real vehicle performance, in different operative road conditions, can be validated through the laboratory dynamic test bench.