PURPOSE: To detect the ground voltage being applied to a high voltage conductor in a switch with high accuracy by interposing a capacitor, which compensates for the temperature variation of capacitance at an insulator part, between inside and outside voltage division electrodes.
CONSTITUTION: Inner and outer voltage division electrodes 3, 4 are disposed coaxially around the insulator 2 of a switch holding a high voltage conductor 1 internally. A capacitor C2 for compensating for the temperature variation of the capacitance C1 between the conductor 1 and the electrode 3 is connected between the electrodes 3, 4. A capacitor C3 having temperature characteristics equivalent to those of the capacitance at the insulator 2 is connected in parallel with the capacitor C2. This constitution compensates for the temperature characteristics of the capacitance C1 between the conductor 1 and the electrode 3.
ABE NORIO
OGUMA SHUJIRO
UCHIDA KENJI
TOHOKU ELECTRIC POWER CO