To reduce a DC transformer facility for an electric railroad by simplifying a current measuring means and eliminating a rectifier negative electrode disconnecting switch board in the DC transformer facility provided with a rectifier system for feeding power to DC load from an AC power source via a transformer, a rectifier and a DC bus bar.
Both of a DC current transformer for a measuring instrument to be provided in a feeder from the rectifier to the DC bus bar and a DC current transformer for a measuring instrument to be provided in a return line from the DC load to the rectifier are eliminated. An AC current measurement value is determined from an AC current effective value measured in one phase on an AC side by a current transformation rate conversion. A DC current arithmetic value is determined from an AC current average value by a transformation rate conversion. A DC voltage measurement value is determined from an output voltage value of the rectifier by a conversion rate conversion of the DC transformer for the measuring instrument. The negative electrode disconnecting switch board of the rectifier is eliminated, and is stored in the rectifier or separately arranged in the vicinity.
| JPH01255444A | 1989-10-12 | |||
| JPH01132432A | 1989-05-24 | |||
| JPH07322624A | 1995-12-08 | |||
| JPH0269675A | 1990-03-08 | |||
| JPS62144076A | 1987-06-27 |
Yoshihide Komada
Kiyoshi Matsuzaki