A Review of Power Transfer Systems for Light Rail Vehicles: The Case for Capacitive Wireless Power Transfer

Abstract

Light rail vehicles (LRVs) are increasingly in demand to sustainably meet the transport needs of growing populations in urban centres. LRVs have commonly been powered from the grid by direct-contact overhead catenary systems (OCS); however, catenary-free direct-contact systems, such as via a “hidden rail”, are popular for new installations. Wireless power transfer (WPT) is an emerging power transfer (PT) technology for e-transport with several advantages over direct contact systems, including improved aesthetics and reduced maintenance requirements; however, they are yet to be utilised in LRV systems. This paper provides a review of existing direct-contact and wireless PT technologies for LRVs, followed by an in-depth critical assessment of inductive power transfer (IPT) and capacitive power transfer (CPT) technologies for LRVs. In particular, the feasibility and advantages of CPT for powering LRVs are presented, highlighting the efficacy of CPT with respect to power transfer capability, safety, and other factors. Finally, limitations and recommendations for future works are identified.

The Safety, Operation, and Energy Efficiency of Rail Vehicles—A Case Study for Poland

“…Finding an optimal solution should also consider the timetable, passenger comfort, traffic conditions on the route, and the durability and reliability of rail vehicles. This analysis serves as a starting point for further work on the energy efficiency of electrified rail transport, aiming to develop an energy optimisation algorithm [2][3][4][5][6][7][8][9][10][11][12].…”

“…The focus was particularly on presenting the feasibility and advantages of CPT for powering LRVs, emphasising its effectiveness in terms of power transmission capability, safety, and other factors. The following requirements for this power transmission system for LRVs were defined [5]:…”

“…Any organisation acting as a railway operator must have a safety management system, which needs to be certified before being introduced into operation [5]. It must then act in accordance with this system's requirements.…”