摘要 |
A power failure section can be accurately detected without depending on a loaded state and application of voltage to the overhead power line can be stopped in a short time when a power failure is detected. An electric car controller includes an overhead power line voltage detector (11), a band-pass filter for detecting a ripple component included in the detected overhead power line voltage, a comparator-1 for comparing the level of the detected ripple component with a predetermined reference value Vref1, a rheotome control circuit (16) and a rheotome (3) which judge that a power failure has occurred if the ripple component is judged to be smaller than the reference value Vref1 based on a comparison result obtained by the comparator-1 and disconnect the overhead power line (1) from a VVVF inverter (6), a second comparator-2 for comparing the level of the ripple component with a reference value Vref2 larger than the reference value Vref1, and a brake chopper (8) and a brake chopper control circuit (17) which operate if the ripple component is judged to be smaller than the reference value Vref2 based on the comparison result obtained by the comparator-2 to suppress the increase of the overhead power line voltage. |