| 摘要 |
<p>PURPOSE:To prevent the main motor of an electric rolling stock from being damaged, by detecting the existence of the abnormal state of an armature chopper with an abnormal state detecting means set in parallel with an armature, prior to the composition of a main circuit including the armature. CONSTITUTION:When desired power command is applied to an electric rolling stock, then a line breaker 21 is closed and a filter capacitor 4 is electrically charged. Then, a difference between the charging voltage of the filter capacitor 4 equal to stringing voltage and both the end voltage of an armature chopper 6 is set, and the difference and a specified reference value are compared with each other. When desired conditions are satisfied with this compared result, then it is discriminated that the armature chopper 6 is sound, and the command for closing a line breaker 22 is generated. On the contrary, when the desired conditions are not satisfied with, then the command for closing line breaker 22 is not generated. As a result, the main motor of the electric rolling stock can be prevented from being damaged.</p> |
