Robust power system stabiliser design using minimax control approach: Validation using Real-time Digital Simulation

This paper addresses the problem of designing decentralized power system stabilisers for interconnected power systems using robust output feedback minimax control techniques. We have considered the problem of designing a robust controller for a generator connected to a multi-machine grid system. To make the controller robust against parameter variations around the operating point, system parameter variations, due to load changes, are represented using integral quadratic constraints (IQCs). The interconnection effects from other machines in the system and local uncertainties are also included in the controller design using IQCs. Generator speed is used as the output feedback variable for the controller, due to the fact that other generator states are difficult to measure. The controller design is validated using a real-time digital simulation (RTDS) facility for a four-machine two-area test system.