AC CURRENT TYPE AUTOMATIC OFF-LINE MEASURING DEVICE FOR ELECTRIC CAR

摘要

PROBLEM TO BE SOLVED: To suppress malfunction output and to improve reliability when a current changes in an AC current type automatic off-line measuring device. SOLUTION: This device comprises a means for detecting an off-line signal by a pantograph current; a device for detecting a current of a main transformer of an electric car; a means 1 for detecting a current difference between a current value of the transformer sample continuously for a certain period of time and its preceding value; a means 2 for deciding a minimum current of the transformer; a deciding means 3 by a current decrease of the transformer; a deciding means 4 by a current increase of the transformer; a means 5 for deciding by a correlation between the minimum current and the decision information by the current decrease and increase, a means 6 for deciding the continuity of the output of the means 5 based on the correlation; and a means 7 for controlling the output of the off-line signal based on the information of the decision of the continuity.