PURPOSE: To connect three vehicles without interfering an intermediate truck with motors and also easily constitute four vehicle body incorporating an idler vehicle between power units.

CONSTITUTION: Vehicles Tp are feeder vehicles having current collecting equipment (a) comprising pantagraphes and in the case of A.C. electric vehicles, feeder systems (b) comprising mainly transformers. Vehicles M on both sides of the vehicles Tp are electricity receiving power cars which are supplied with electricity by the vehicles Tp and are driven by electricity receiving units (c) represented by inverter units, for example. Total eight motors of those of four trucks are driven by these feeder systems (b) through the electricity receiving units (c) on both sides, and a power unit is composed of three vehicles. Each of vehicle numbers of vehicles constituting a power unit is circled by a circular. A connection structural idler vehicle body T is generally connected between power units, that is, between the electricity receiving power vehicles M of units which are different from each other in types so that two power units may be directly connected to each other.