Distributed communication-based Model Predictive Control for long-term voltage instability

This paper deals with a form of long-term voltage instability which can arise from uncoordinated control actions taken by interacting voltage controllers. An effective coordination paradigm, based on Model Predictive Control (MPC), is proposed in order to properly coordinate local control actions taken by Load Tap Changing transformers (LTCs). This coordination is achieved by exchange of information on local planned LTC moves among immediate neighboring control agents (CAs) only, within a prediction horizon. Each MPC-based voltage controller, knows only a reduced-order local hybrid system model of its own area, and uses approximate models for its immediate neighboring areas, as well as even more approximate models for remote areas. Simulation results on well-known Nordic32 test system illustrate the good performance of the proposed real-time coordinating voltage controller.