Development of a high-speed current limiter for a 6 kV distribution system and evaluation of its effectiveness

✍ Scribed by H. Kurioka; T. Genji; M. Isozaki; H. Iwai; M. Yamada

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 220 KB
• Volume: 125
• Category: Article
• ISSN: 0424-7760
• DOI: 10.1002/(sici)1520-6416(19981130)125:3<11::aid-eej2>3.0.co;2-3

✦ Synopsis

We have developed a high-speed fault current limiting equipment for a 6 kV distribution system. The main components of this equipment are a high-speed vacuum switch (VCB) and gate turn-off thyristors (GTO) connected in parallel, and a current limiting impedance with low linear resistance in parallel with the switch. The usual load current is carried by the VCB. In case of a power system fault, the fault current is commutated to and interrupted by the GTO on opening the VCB. Tests confirm that the equipment can interrupt an estimated short-circuit current of 13 kA rms by limiting to less than 3.5 kAp. The interrupt time was less than 2 ms. This response is about 100 times faster than that of conventional mechanical circuit breakers.

The fast interruption current limiter can protect distribution systems within a few ms of a severe short circuit fault occurrence. The primary operational benefit of this equipment is the reduction of instantaneous voltage drop at the bus or on sound lines and of current stress on power system equipment during a power failure.