Estudo do Efeito Ferranti em linhas de transmissão longas

Abstract

Voltage control in large transmission systems is a major concern for network flexibility, security and reliability. Interruptions in the supply of electric power generate great damages for both the final consumers and the concessionaires of electric power, and these interruptions should be avoided to the maximum, since the companies responsible for the electric power transmission service is regulated and supervised by the Agency National Electric Power - ANEEL applying the same penalties for the quality of the service provided. The use of long transmission lines is a common practice in the country when there is no source of power generation near the center of consumption. In Brazil the concentration of energy consumption occurs in specific regions in the territory and the generations are of great relevance and by water use in distant and anti-consumption locations. One of the singularities of high voltage long extension transmission systems is linked to the difficulties associated with the control and voltage regulation offered in the consumer bars. In the case of unloaded or light load operation, which is in force during the energisations or due to load rejections, the capacitances associated with these lines sometimes impose unacceptable increases in the voltage of the bus bars. Within the SEP, there are several fundamental equipment to guarantee the quality of the electricity delivered to the consumer. One of these devices is the shunt reactor, whose main function is to regulate the voltage in the transmission line by compensating for excess reactive power in large transmission lines. In this work, we performed the analysis of the voltage caused by the transmission lines working in vacuum, and consequently their behavior after the insertion of the shunt reactors to the reduction of the same to accessible levels. We used the software Alternative Transients Program (ATP) to simulate the results and compare them to the problem.