| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem of DC transformation equipment for electric railroads that the trolley voltage increases under a light load even without generation of regenerative power and a regenerative power absorption apparatus starts a power absorption operation, resulting in wasteful consumption of power.SOLUTION: A detected trolley voltage value is compared with a preliminarily set value of an absorption initiation voltage, and, when the trolley voltage value is higher than the set value, signals are outputted into one input terminal of an AND circuit. A ripple based on an output pulse of a rectifier is detected by inputting the detected value of the trolley voltage to a ripple detection portion. When the ripple decreases to a specified number or smaller, signals are outputted into the other input terminal of the AND circuit. An operation of absorbing regenerative power is initiated at the time of establishment of the logical product. |
