Robust optimal transmission switching for wind farm‐integrated power systems from a perspective of steady‐state security region

Abstract

Optimal transmission switching (OTS) is a new method in improving operational security and economy of power systems. However, with continuous improvement in wind power penetration level, how to rationally describe the uncertainty of wind power play an important role in determining robustness of the OTS model. Against this issue, a system robust domain (SRD) developed by steady-state security region is proposed to model the uncertainties of wind power outputs in OTS. This modelling method focuses on the robust domain of system rather than the robust intervals of variables in conventional robust optimisation, thus overcomes the high dependence of conventional robust optimisation on accurate estimation of each uncertainty intervals. SRD-OTS is formulated and a decomposition algorithm is employed to obtain the optimal solution. The obtained optimal solution can maintain the operational security in the worst case of wind power outputs and minimize operational cost with the forecasted wind power outputs. In addition, robustness of the proposed SRD-OTS can be adjusted by an uncertain budget. The numerical results on the IEEE test system verify effectiveness of the proposed SRD-OTS and show that the optimal solution is still robust with a relative lower accuracy of wind power prediction.