A rapid fitting method of DSR based on characteristic quantities of the maximum power angle curve

Fitting method is the most basic method of calculation of boundary hyperplane of the power system DSR(dynamic security region). Because of the characteristics of high precision but huge amount of calculation and large time-consuming, it can only be calculated off-line and applied online. Based on selecting the appropriate characteristic quantity of the power-angle curve, this paper finds a law that the geometrical distance of the injection point to the critical point and the characteristic quantity of maximum power angle curve satisfies a relationship of cubic function. By solving the law function, the estimated critical injection power point can be calculated more quickly, and then the approximate hyperplane coefficients can be obtained. In the end, the feasibility of the proposed method is verified by the case of the IEEE 4-generator 11-node system. Simulation results show that compared to the traditional fitting method, the computing time and the error is only about 30% and 5% separately, and can meet the project needs.