Abstract: To prevent demagnetization of a permanent magnet synchronous rotating machine, a rotating machine control device according to the present invention is a rotating machine control device comprising: a power converter having a switch part on each of a positive side and a negative side for each phase; and short circuit detection unit for detecting a short circuit of the switch part, wherein a command to turn on positive-side switches and negative-side switches of a plurality of phases of the switch part is issued in the case where the short circuit detection unit detects the short circuit.

Abstract: Provided is a high mobility railroad vehicle system configured to reciprocally carry out a direct drive between a non-electrically driven section and an electrically driven section without installing new facilities such as oil supply equipment and without considering distinction between the non-electrically and electrically driven sections. A railroad vehicle system is provided with an overall control apparatus to respectively control an external electric power supply means, an internal electric power supply means, an electricity storage means, electric power conversion means and a motor driving means. The railroad vehicle system judges or previously notifies as to whether the present driving railroad section is the electrically driven section or non-electrically driven section in accordance with driving position information received from a position information generation means such as a ground facility on a railroad equipped outside of the vehicle and a global positioning system (GPS).