This paper presents the variation of condition number `K' on ill-conditioned power system with series flexible ac transmission system device, TCSC (Thyristor Controlled Series Compensator) with varying degree of compensation. Case studies are carried out on IEEE 14-bus test system by gradually increasing the resistance part of the line data of IEEE 14-bus system is to create an ill-condition in the system.

Networks which have the above features are described as ill-conditioned systems. In other words, a small change in input parameter produces a large change in the solution. It was mentioned by Gotham and Heydt (1998), and Hingaroni and Gyugyi (2000) that the Flexible Alternating Current Transmission System (FACTS) devices influence the power system network parameters extensively. To the best of our knowledge no attempt has been made in examining the impact of FACTS devices on the ill-conditioned power systems. This motivated us to study the effect of series compensation device (Thyristor-Controlled Series Compensator, TCSC) on the ill-conditioned power systems. In this paper, we present the effect of TCSC with varying degree of series compensation on the condition number (K).

A computer formulation of a problem is defined to be ill-conditioned if the computed values are very sensitive to small changes in input value. A matrix may have some eigenvalues that are very sensitive and some that are comparatively insensitive. Condition number (Durgaprasad et al., 1982) is a number which defines the condition of a matrix with respect to the computing problem.

Electrical and Electronics Engineering Journal, Flexible Alternating Current Transmission System (FACTS), Condition Number, Thyristor-Controlled Series Compensator (TCSC), Newton-Raphson Power Flow, Diagonal Dominance, Firing Angle Power Flow Model, Jacobian Matrix, Load Flow Calculation Method, Power Flow Control.