摘要 |
<P>PROBLEM TO BE SOLVED: To use one set of a chopper circuit and not to make the circuit enlarged, and to enable self-operated traveling in a section without overhead wire, even if the circuit is broken down. <P>SOLUTION: A switch 11 is provided between a neutral point of a winding of an AC motor 72 connected to for example, output of an inverter 62 of a plurality sets of inverters provided and an energy storage device 9. When at least the chopper circuit 8 and its control device break down, the inverter 62 is made to operate as a chopper circuit by turning OFF the switch 11 and connecting the inverter output to the energy storage device 9 through the switch 12, while turning OFF the switches 10a and 10b and separating the chopper circuit 8. <P>COPYRIGHT: (C)2012,JPO&INPIT |