Performance Evaluation of Thyristor Controlled Series Capacitor Based Controller for Power System Damping Pawan Kumar Yogi , Ravi K.Ranjan Annapurna Bhargava Asst. Professor, EED, ACEIT,Jaipur Assot. Professor, EED, UCE,Kota yogipawan5@gmail.com ab_eck@sify.com ranjanrex.ranjan@gmail.com Abstract— Power system damping through coordinated design of a power system stabilizer (PSS) and a thyristor controlled series capacitor (TCSC) –based controller is present in this paper. The design problem of the coordinated PSS and TCSC based controller is formulated as an optimization problem and optimization based linear control design technique isemployed to search for optimal controller parameters. The performance of different optimization techniques is compared in terms of finding quickly and enhance the stability by reducing the settling time. Optimization based tuning only changes the value of the controller parameters and not the controller structure itself. The coordinated design is tested in a single machine infinite bus system and the results are compared with conventional PSS and individually tuned PSS and TCSC. The time domain analysis and simulation results are presented to show the effectiveness of proposed technique in designing in a coordinated controller Keywords— Power system stabilizer; FACTS devices; TCSC; Power oscillation damping. I. INTRODUCTION The development in the power electronics field introduced use of flexible ac transmission systems (FACTS) controller in power systems. FACTS controllers are used to control the network condition at a super lightening speed and this characteristic of FACTS is enhanced to improve the stability in entire power system. Thyristor restricted succession compensator is one of the essential members of FACTS family that has been exponentially come out with long transmission lines by the utility modules in today’s power systems [1]. TCSC perform various roles in the operation and control of modern power systems, such as rescheduling of power flow, reducing unsymmetrical components, decreasing total power loss, providing voltage stability, limiting short-circuit currents, reduce sub-synchronous resonance (SSR), control damping the power oscillation and improve transient stability. The TCSC is an alternative to SSSC above and like an SSSC, it is a very important FACTS Controller [2]. It has been in use for many years to increase line power transfer as well as to enhance system stability. TCSC is a series FACTS device which allows rapid and continuous changes of the transmission line impedance. The development in the power electronics field introduced use of flexible ac transmission systems (FACTS) controller in power systems. Some small signal stability studies the linear model of Phillips-Heffron is used a power system. In spite being of a linear model, it is quite accurate for the study of low frequency oscillations and stability of power systems [3]. The procedure of FACTS controller parameter tuning has always been a complex exercise. A number of techniques have been reported till now pertaining to design problems of conventional power system stabilizers namely: the Eigen value assignment, mathematical programming, gradient procedure for optimization and also the modern control theory. Unfortunately, these techniques are time consuming as they are performed by the iterative method and require heavy computation burden and slow convergence. II. SMIB with TCSC Controller The Single Machine Finite State system can qualitatively demonstrate the significant properties in the behavior of a multi-machine system and is convincingly simple to examine [4]. Henceforth it is conventionally accepted for describing the universal concepts of power system stability, influence of arbitrary factors upon stability and alternative concepts of controllers. We consider particular SMIB power system arrangement as portrayed in _______________________________________________________________________________________________ _______________________________________________________________________________________ 200 IJFRCSCE | January 2018, Available @ http://www.ijfrcsce.org (ICATET 2018) International Journal on Future Revolution in Computer Science & Communication Engineering ISSN: 2454-4248 Volume: 4 Issue: 1 200 – 204