| 摘要 |
<p>1,093,021. Fault locating; impedance measuring. ENGLISH ELECTRIC CO. Ltd. Jan. 29, 1965 [Feb. 5, 1964], No.4863/64. Heading G1U. In an arrangement for determining the impedance, or length to a fault, of a line, two vector quantities dependent on both current and voltage are derived, and the phase angle between them measured to give an indication of impedance or length. A first signal proportional to line current is applied to first primary windings 13, 14 of tranformers 11, 12 and a second signal proportional to the voltage is applied to second primary windings 16, 17. The outputs from secondary windings 24, 25 are compared in a phase comparator 21 and fed to an indicator. The system is calibrated by means of resistors 19, 20. In a modification one of the resistors may be omitted and the phase of a single vector dependent on current and voltage is compared with that dependent on the remaining resistor.</p> |
