PURPOSE: To test at a high speed an exact load switching with a suffient DC equivalent property by switching alternately the polarity of DC impressed to a vacuum switch.
CONSTITUTION: After the maximum current I1 flows by dissociation of a vacuum switch VI1 of the primary side of a transformer T, an arc current flows in a period of time tarc. On the other hand, in the secondary side of the transformer T, a constant DC arc current I2 whose energy coincides with an arc energy of the primary side flows through a resistance R, etc. constantly in a turn-on period (t) of the switch VI1, to a vacuum switch VI2 through a rectifying circuit REC and a polarity switching circuit TS. Aslo, the polarity of this current I2 is switched by the circuit TS. According to said constitution, an exact load switching can be tested at a high speed with a sufficient DC equivalent property.
TAMAKI NOBUAKI
KANOU MASAYUKI
SENBA KATSUAKI
