Optimal placement of FACTS devices for the improvement of technoeconomic performance of power networks

In contemporary power system studies, the optimal allocation and utilisation of Flexible AC Transmission System (FACTS) devices are imp0l1ant issues primarily due to their cost as well as their multifunctional capabilities. In this thesis, a depth literature review regarding the technical contribution of FACTS devices along with their allocation methods in power systems is presented. Four types of FACTS devices (Static Var compensator (SVC), Thyristor-Controlled Series Capacitor (TCSC), Thyristor-Controlled Voltage Regulator (TCVR), and Thyristor-Controlled Phase Shifting Transformer (TCPST)) are considered for optimal placement in a multi-machine power system to reduce the overall costs of power generation. The placement methodology simultaneously considers the cost of generated active and reactive powers and the cost of selected FACTS devices for a range of operating conditions. The annual Load Duration Curve (LDC) has been used in the selection of the operating conditions in order to make the proposed allocation beneficial over the year and to remove any bias in the device selection. Two global optimisation techniques: the Genetic Algorithm (GA) and a new method based on the Low Discrepancy Sequences (LOS), are employed to solve the allocation task. The Optimal Power Flow (OPF) is integrated into the proposed optimisation methods in order to solve for the cheapest generation dispatch. The Net Present Value( NPV) method is then utilised to assess the economic value of the solution. The NPV evaluation study includes a detail discussion of the uncel1ainties involved in the NPV main parameters. The system steady state propel1ies in terms of voltage profile and power transfer are investigated after the allocation of the devices in order to avoid any adverse effects of such allocations. The Voltage Security Margin (VSM) is used in the voltage profiles assessment which measures the relative voltage strength. In addition to the steady state performance assessment, the system dynamics has been examined as well after the placement of the devices in order to find out the devices impact on the system stability, both small signal and transient, as the contribution of such devices to damping the electromechanical oscillation represents a crucial benefit. In this assessment, a systematic explanation of the FACTS devices incorporation in the muItimachine power system is presented in addition to a method of coordinated tuning of the system damping controllers. Furthermore, an observability study is performed for the selection of the FACTS devices damping controllers input signals.EThOS - Electronic Theses Online ServiceGBUnited Kingdo