Dynamic Difference Correction Tracing Control Algorithm for Bulk Capacity Nonlinear Elements of Power Systems

Large scale application of new energy resources and flexible transmission and distribution equipment are aggravating the nonlinearity and dynamic nature of large grids. To increase the flexibility and reliability of power system control, this paper proposed a tracking control algorithm based on dynamic difference correction for time-varying parameters of power system nonlinear elements. Extra and ultra high voltage magnetically controlled shunt reactors(MCSR) were used as an example of nonlinear elements to demonstrate the performance of the proposed algorithm; the control objectives are to maintain voltage stability, suppress over-voltage at power frequency, regulate voltage smoothly and quickly, prevent and reduce the voltage oscillation. Based on the extensional model and curvilinear regression algorithm, the nonlinear regression equation in dynamic time-varying parameters was created, considering the relevance of power system and MCSR. Following the mapping transformation, analytical solution of parameters tracking formula was constructed, and time varying parameters difference correction algorithm was used to further improve the mapping and tracking precision. The algorithm does not need iteration. Taking MCSR as an example, computer simulation in advanced digital power system simulator(ADPSS) verified the effectiveness of the control algorithm. The algorithm can help to improve dynamic control effects of nonlinear equipment and provide reference for the controller design of bulk capacity nonlinear element in power systems.