Transmission Line Capacity Improvement Using Thyristor Controlled Series Compensation Device Considering Voltage Stability Analysis

Abstract

In this paper, the interior point method (IPM) is applied to the optimal reactive power planning (ORPP) problem using the thyristor controlled series compensator (TCSC) device with consideration of voltage stability with handling the improvement of transmission line capacity in electrical network. To improve this case of study, two other objective functions are associated. The first is the angle deviation minimisation problem; it minimises the difference between the sending and receiving bus angles. And the second one is voltage deviation problem which aims to improve the system voltage profiles. The choice for these associate objective functions is defined by the most influence of bus angles and voltages to improve the system transmission line capacity. Also, the proposed algorithms satisfy various constraints, which are: power flow equations, generator voltage limits, switchable capacitor banks, transformer tap changer limits and transmission line limits. The fast voltage stability index (FVSI) is used to identify the critical lines to install the TCSC controllers. The methodology has been tested in the equivalent Algerian electrical power systems 114 bus. The simulation results show the effectiveness of the proposed approach for improving the reactive power planning problem.