DEVELOPMENT OF A NEW MULTI-DIVIDED TYPE OF COMMUTATING ELEMENTS FOR FAULT CURRENT LIMITERS ON DISTRIBUTION LINES

An extremely large short-circuit current flows through equipments in the power distributing system under a fault, in comparison with the normal current. As the equipment is designed and manufactured to withstand this short-circuit current, its costs and dimension can be reduced by suppressing this current as low as possible. The authors, accordingly, have developed a new type of commutating element that can be used repeatedly in order to develop fault current limiters (FCL) to be operated on distribution lines. Operating tests were carried out on the commutating element combined with a conducting element in a circuit equivalent to the line voltage of 6.9kV and the short-circuit current of 12.5kA, in which the FCL was able to limit the actual peak current to 12kA, or one third under the condition of the peak current of 32.5 kA in no use of the FCL.