Enhancing the performance of power system transmission network

Today’s energy scenario, demands a significant change in the transmission network. As the demand for electrical energy increases day by day, new sources for generation of electrical energy are being probed. This increased generation of electrical energy must ultimately reach the end consumers. This can be done by installing new transmission lines. But, the planning of new transmission lines is inhibited by various factors like right of way, ecological elements and increased expense of installation. Therefore, the increased generated power has to be transferred to the end consumers only with the existing transmission lines. This has led to the transmission lines operating nearer to the thermal limits and voltage limits more often. Hence, the existing transmission lines are prone to stability limit violations. Generally, the problems of voltage collapse and black outs are increasing. Moreover, the reactive power compensation is also the need of the hour. This decreases the transmission line losses effectively. The increased power transfer in the existing transmission lines is also affected by the network constraints. The other scenario that has to be viewed in the transmission sector is the policy of deregulation practiced in the present power system. Deregulation of the power industry has led to the transformation of electricity into commodity. In earlier days, power industry was under monopoly and the pricing was fixed by the Government policy. Due to privatization of power sector, different private sectors are interested in delivering power to the end consumers at low cost along with reliability and quality. This leads to the congestion in transmission lines. The problem of congestion has to be tackled by the transmission system. The significant change in the present-day transmission system has led to the increased power transfer in the existing transmission lines without violating the stability limits.
A forty-eight pulse STATCOM evolved on two level gate turn-off thyristor based voltage source converters (GTO-VSCs) topology to be operated at fundamental frequency switching modulation is employed to have higher voltage gain in the midpoint of the transmission line enabling to achieve reasonable power gain in the system.