Abstract
The secure operation of power system has become a topmost issue in today's largely complicated interconnected power systems. This chapter presents the implementation of grey wolf optimization (GWO), teaching-learning-based optimization (TLBO), biogeography-based optimization (BBO), krill herd algorithm (KHA), chemical reaction optimization (CRO), and hybrid CRO (HCRO) approaches to find the optimal location of various FACTS devices such as thyristor control series compensator (TCSC), thyristor control phase shifter (TCPS), and static VAR compensator (SVC) to solve optimal power flow (OPF) and optimal reactive power dispatch (ORPD) in power system. In this chapter, a standard IEEE 30-bus test system with multiple TCSC and TCPS and SVC devices are used for different single and multi-objective functions to validate the performance of the proposed methods. The simulation results validate the ability of the HCRO to produce better optimal solutions compared to GWO, TLBO, BBO, KHA, and CRO algorithms.
TopIntroduction
In the last few years, voltage collapse problems in power systems have been of permanent concern for electric utilities: several major blackouts throughout the world have been directly associated to this phenomenon. The voltage instability can occur when a power system is heavily loaded in transmission lines and/or lacks in local reactive power sources (Shin et al., 2007). The capacity of transmission lines is becoming the main bottleneck of electricity transmission in the deregulated power industry. The competition of electricity may aggravate load ability of some transmission lines. To meet the load demands in a power system and to satisfy the stability and reliability criteria, the existing transmission lines must be utilized more efficiently. The purpose of the transmission network is to pool power plants and load centres in order to supply the load at a required reliability and maximum efficiency at a lower cost. A technically attractive solution to above problems is to use some efficient controls with the help of FACTS (Flexible AC Transmission Systems) devices.
The location of FACTS devices can be based on static or dynamic performances of the system. The sensitivity factor methods are generally used to find the best location to enhance the static performance of the system. FACTS offer a viable solution to these problems, and are now finding wide usage in power systems worldwide. In the deregulated power industry, private power producers are increasing rapidly to meet the increase demand. The purpose of the transmission network is to pool power plants and load centers in order to supply the load at a required reliability, maximum efficiency and at a lower cost. As power transfer increases, the power system becomes increasingly more difficult to operate and insecure with unscheduled power flows and higher losses. FACTS (Dutta et al., 2016; Kavitha & Neela 2017) devices such as Static Var Compensator (SVC), Thyristor Controlled Series Compensator (TCSC) and Thyrister controlled phase shifter (TCPS) can be very effective for power system security. Proper location of SVC, TCSC and TCPS plays a key role for enhancement of system performance without violating the security of the system.
In this chapter, the optimal location of thyristor based FACTS controllers (SVC, TCSC and TCPS) have been introduced for the OPF formulations. The basic objective of OPF is to find proper adjustments of the control variables that would minimize the fuel cost.