Damping in Low Frequency Oscillations by using PSS and TCSC in WSCC9 Bus System using MATLAB Software

Power systems are interconnected through the long distance tie lines. Transmission line is used to transfer or exchange a large amount of electric power. Due to restriction on building new line, transmission lines of power systems are becoming increasingly stressed. Due to stressed system, power system losing its stability. So for maintaining power system reliability, Security and good performance the rotor angle stability improvement is essential. The paper entitled simulating a model of a complete WSCC9 bus system with PSS (Power System Stabilizer) and TCSC (Thyristor control series capacitor). Generic PSS is used on all three generators. Simulation of complete WSCC9 bus system with generic PSS and TCSC is done in MATLAB (R2012b) software. Fault should not lead to tripping of generating unit due to loss of synchronism. When electrical load is suddenly changes then mechanical power cannot change instantaneously because of its moment of inertia. Therefore, in a small duration generator rotor feels an oscillation that have to be damp. PSS (Power system oscillation) and TCSC (Thyristor controlled series capacitor) controller is used to damp such kind of oscillations in multi machine system. Thus simulation of WSCC9 bus system with PSS and TCSC controller is modelled. Thus one can reduce damping in WSCC9 (western system co-ordinate council) bus system in MATLAB software.