21-09-2008, 09:45 AM
With the increasing demand for electric power, the economics of power transmission requires the use of high transmission line voltages. This leads to escalation of cost for conventional CTs and PTs.This paper provides an economical alternative, for the use of CTs and PTs for the measurement of current and voltage. The method is an optical method using lasers. The method employs two types of devices; free path and enclosed path devices. The basic principle of the optical method is based upon magneto-optic effect, electro optic effect and the electro gyration effect.This paper concludes with the suggestion for future development. Instead of using free path, the enclosed path method is suggested. A more highly developed version of the devices should provide a convenient, portable, large bandwidth, research tool for diagnostic use. Eventual development could lead to an acceptable instrument for long-term operational use on the power system. Such an instrument would offer the advantages of considerably improved performance over conventional devices, at much lower cost..