Fast-Swap Charging: An Improved Operation Mode For Catenary-Free Light Rail Networks

This paper introduces the concept of fast-swap charging (FSC), an operation mode designed to improve the operating cost-efficiency relation in on-board-powered light rail (LR) networks. The main concept is to swap the depleted energy storage units for fresh, pre-charged units in every cycle after the LR vehicle arrives at its terminus. The proposed operation mode allows the empty energy storage components to be charged at low electricity-demand periods, such as at night, so that a cheaper kWh tariff is accessed. Energy efficiency models capable of assessing the energy efficiency are developed as a framework for practical case studies. Finally, a case study illustrating the effects of different operation modes on the selection and optimal sizing of energy storage components, and the energy efficiency of the Zhuhai route, China, is included. The results show that the proposed FSC outperform the counterparts in term of average operating cost per year while obtaining a similar efficiency.