Keywords: thyristor controlled series capacitor, TCSC, reactance characteristics curve, power angle curves, split TCSC, micro tuning, reactance tuning, transmission lines, FACTS compensators, power transfer, firing angles, simulation
Micro tuning of reactance by split TCSC on transmission line
The TCSC is a form of FACTS compensator that improves power transfer capability by regulating transmission line reactance. Proper tuning of TCSC results in the variation of inductive/capacitive reactance along with resonance region. A difficulty is observed on tuning the TCSC device; large change in TCSC reactance at critical region (nearby resonance region) prohibits possible fine control of power transfer over the transmission line. This paper therefore investigates the difficulties in tuning of single TCSC in critical region and alternatively proposes split TCSC operation which offers micro tuning of the line reactance. The micro tuning allows for wider degree of compensation over single TCSC operation. The study is carried out on a MATLAB platform and split TCSC results are compared with single TCSC. The simulated reactance characteristic and power angle curve over varied range of firing angles establishes wider degree of possible compensation; a striking benefit of Split TCSC operation.