Chaveamento controlado aplicado ao religamento rápido de linhas de transmissão.

Abstract

A new method for controlled reclosing of transmission lines with shunt reactive compensation is proposed in this thesis. The method is based on simple techniques for analysis of voltage signals required to control the switching operations. It consists in applying modal transformations for separating the frequency components contained in the signals being analyzed. As a result of its application, smaller switchings surges are obtained. Moreover, the method determines the extinction time of single and double-phase to ground faults, which account for more than 80% of faults in 500 and 750 kV transmission lines at the Brazilian Power System Grid. By using the proposed approach, it is possible to prevent reclosing onto fault. After identifying the fault extinction time, it is possible to reclose the line and minimize the dead time in which it is out of service. This reduces the power system restoration time, increasing its reliability and availability. As an application of this methodology, a device to control the line reclosing was implemented and evaluated in a Real Time Digital Simulator (RTDSTM). In addition, an o ine version of the method was implemented for parametric and sensitivity analyzes by means of actual oscillographic data and digital simulations using EMTP (Electromagnetic Transients Program). Data from the Brazilian Power System Grid were used to produce some case studies and the results attest the e ciency of the method to identify the fault extinction time as well as to mitigate the switchings surges, regardless of the parameters evaluated, such as the degree of line compensation, fault resistance and fault location.