design and application of ftsmc to improve stability of power systems with dfig and pv in the presence of tcsc

In this paper, a nonlinear control law is presented to improve the stability of the power networks which include double-fed induction generators (dfigs) and photo-voltaic (pv) cells in the presence of thyristor controlled switch capacitor (tcsc). the proposed control law is based on the finite-time sliding mode control (ftsmc) theory. applying this controller provides supplementary damping to reduce transient oscillations of power systems. this control scheme is robust against variations in the system topologies and parameter uncertainties. in sliding mode control, the use of a fractional sliding surface and the optimal adjustment of its parameters, instead of the common sliding surfaces of the correct order, causes a more accurate adjustment of the sliding surface according to the increase in the degree of freedom, results in the improvement of tracking speed and accuracy.  in comparison with smc, the proposed controller results in less chattering and less settling time. the performance of this control law is independent of the selection of operating point, compare to linear control design methods. moreover, the damping speed is higher, and the required time to reach the stability is lower. a time simulation is carried out on the 39-bus new england system to show the effectiveness of the controller. a comparison is also made between the linear control method and the traditional sliding mode control (smc) design technique.