| 摘要 |
<p>PURPOSE:To smoothly operate an electric railcar by detecting the output voltage of a power converter, and reducing the level of the current command signal when the output voltage becomes higher than the preset voltage level. CONSTITUTION:AC is converted into DC V by a power converter 10, and the DC is supplied to a main motor 11 of an electric railcar. An armature current I is detected by a current detector 14, fed through a current antiover circuit 15 and an adder 16 to a current control unit 12, thereby suppressing the abrupt increase of a current command EI. Further, an AC voltage detector 20, a DC voltage detector 21 and a discriminator 22 are provided. Thus, the output voltage V of the converter 10 is detected by the detector 21, the current of the main motor 11 is reduced on the basis of a current reduction signal DELTAE from the discriminator 22 for the prescribed time when the detected voltage becomes higher than the preset voltage level in the discriminator 22 at slipping and derailing time. The control for returning to the original is performed again at the prescribed time, and the delivery of the signal DELTAE is stopped at the power driving and regenerative starting time.</p> |
