Inter-system checking device

Abstract

Abstract PURPOSE: To improve the reliability of a device, by providing discriminating levels with dead zones so that a difference between selected generators cannot be generated, and by discriminating the device with an error generated by active power. CONSTITUTION: When a breaker CBL is interrupted, then power is excessively fed and frequency is heightened. The heightening of the frequency is computed by a voltage-momentary value obtained via voltage transformers PT 1 ∼PT 3 , and at the same time, through current informations, active power is computed and is fed to a central unit C o from signal wires C 1 ∼C 3 . By the central unit C o , based on the active power(P 1 ∼P 3 ) and the frequency(f l ∼f 3 ), it is discriminated that generators G 1 ∼G 3 are connected to systems and are normal when the deviation between the frequencies f 1 ∼f 3 is within a set range sides, when the deviation exceeds the set value, then the generators G 1 ∼G 3 are selectively interrupted, and the frequency is prevented from being heightened. Besides, when the average value of the frequencies f l ∼f 3 exceeds a discriminating level, then an error included in the sum of the active power of the generators G 1 ∼G 3 and a comparison value are compared with each other, and according to the result of the discrimination, the generators G 1 ∼G 3 are selectively interrupted. COPYRIGHT: (C)1989,JPO&Japio

Inventors

• 👤 Goo Nohara
• 👤 Masuo Goto

Bibliographic Details