Deregulated electric power industries have changed the way of operation, structure, ownership and management of the utilities. The existing power transmission networks may not have been able to accommodate all the new scenarios for electricity trades.
The energy transaction in open access environment may lead to unexpected amount and direction of power flow through some transmission corridors, resulting in the need for some load to be dropped momentarily in order to maintain the system security.
It is further endangered by relative decline in transmission expansion due to requirement of huge investment coupled with the problems in acquiring right of way for the new transmission facilities and the concerns towards environment and cost. It may not be ideal for the power generation company to drop some loads, which may cost them penalties while the system operates near its operating limits in terms of security.
Curtailment of loads under contract, costs the power companies, a reduction in their regular tariffs. It is always preferable to have minimum curtailment in the system at all as it is better for the system reliability and fulfilling the contractual obligations; therefore, load curtailment reduction is an important issue to be addressed in electricity markets.
With increasing demand and supply in the power systems, maintaining the security, stability and reliability have become a challenging task, specifically in the emerging electricity market scenario.
The basic challenge in the evolving deregulated power system is to provide a transmission network capable of delivering contracted power from suppliers to consumers over large geographic area under market forces controlled, and continuously varying patterns of demand and supply. Flexible AC Transmission Systems (FACTS) are being popularly used by utilities due to their capability to enhance power system static as well as dynamic performance.
Author: Wajahat Qazi, Hassan