Joachim Winter

Inductive power supply for heavy rail vehicles

Electrical railway systems are characterized by the energy transfer from fixed installations of the railway energy supply source to the mobile consumers. Todays conventional versions are always characterized by contact-based energy transfer. In the following, the initial approach for a energy transfercontactless energy transfer for standard gauge railway vehicles is set out. Building on the railway specific requirements of an energy transfer system, a first system draft is outlined. The feasibility for introducing such a contactless transmission system depends on the overall costs arising during the life cycle in comparison with conventional systems. For this reason, the costs of todays installations are considered, and related pros and cons of the alternative transmission systems are discussed. In addition, the perspectives for the introduction of contactless energy transfer are evaluated.

Challenges in High-Power Railway Applications using Inductive Power Transmission

Under the generic term ‘Next Generation Train - NGT’ the German Aerospace Center (DLR) has introduced vehicle concepts for various railway applications. All train concepts have in common that the required energy is supposed to be supplied through a catenary-free energy transfer system that uses inductive power transmission. The transition from a sliding electrical contact to catenary-free current transmission requires fundamental changes to the overall design of the power supply system primarily due to the different energetic conversion processes needed for an inductive power transmission. However, existing technological limitations, especially power electronics, have a serious impact on the system design. The challenges related to the dimensioning of the track-side power supply system, considering technological limitations of today’s equipment are discussed in this paper.

Contactless energy transfer for main-line rail vehicles

In the context of an increasing importance of electric mobility with the aim to reduce greenhouse gas and noise emissions, railway operators intensify efforts to replace diesel vehicles with locally emission-free electric traction. Therefore more and more tracks need to be electrified. These electrified lines are the primary object of this paper. In 2010, the total electrified track length worldwide amounted to 262,000 km. For main-line electric rail vehicles the power is almost exclusively transmitted through a sliding contact between roof-mounted pantographs and overhead catenary systems. In main-line railway networks both alternating current as well as direct current is applied. Direct current systems (DC systems) hold a share of about 37 % of electrified railways worldwide. However, due to the comparatively low level of nominal voltages of not more than 3 kV, one has to consider that DC systems are inappropriate for high performance main-line operation and especially in high-speed applications. For alternating current systems (AC systems) frequencies of either 16.7 Hz or 50 Hz are applied. Worldwide AC systems using 50 Hz at a nominal voltage of 25 kV are predominant. The global share of 25 kV AC systems is approximately 46 % of the electrified railway networks.