Summary of Feeding Systems

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AT Feeding System

(1)Suitable for supplying the electricity to large-capacity loads because the feeding voltage can be made higher than the contact wire voltage.
(2)The Traction Substation interval can be made longer than other Feeding Systems.
(3)There are no BT sections.


Coaxial Cable Feeding System

(1)Exhibits the largest drawing effect due to a large coefficient of mutual induction between coaxial conductors, thereby providing a reduction in telecommunications induction.
(2)There are no BT sections.
(3)OCS configuration is simple; suitable for long tunnels.
(4)Cables are costly.


Simple Feeding System

(1)Simplest feeding circuit configuration.
(2)There is a large inductive obstruction on the telecommunication lines
(3)Countermeasures such as protection of insulators for flashover are required.
(4)The rail potential is theoretically higher than for other Feeding Systems.


Simple Feeding System with NF (RC)

(1)The feeding circuit impedance and rail potential are reduced a little more than the basic model by providing an NF (RC).
(2)Greater shielding effect against telecommunications induction than the basic model.

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AT Feeding System

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