Coordination of SVC and PSS for stability enhancement of DFIG-based offshore wind farm connected to a multi-machine system

This paper presents an implementation of Static Var Compensator (SVC) & a Power System Stabilizer (PSS) to improve the transient stability of a DFIG-based offshore wind farm (OWF) connected to a multi-machine system. In wind farm connected grids, maintain the stability of grid and wind farm during transient disturbances is a serious issue. Due to grid faults wind DFIG trip and synchronous machines start oscillation due to insufficient damping. To check out the stability of proposed system a three-phase to ground (LLLG) fault has been taken at bus number six of three machine nine bus system. The test system is modelled and simulated in MATLAB/Simulink platform. In absence of SVC during three phase to ground fault DFIG trip due to the reduction in its terminal voltage below a critical value. But in presence of SVC wind farm protection system does not trip DFIG due reactive power support. And in presence of both SVC & PSS synchronous machine oscillations are also damped, hence settling time and overshoot of a system also reduced.