Large-Scale Solar PV Converter Based Robust Wide-Area Damping Controller for Critical Low Frequency Oscillations in Power Systems

Integration of large-scale renewable energy sources in legacy power system has negative impact on inertia and low-frequency oscillations (LFOs). Critical LFO modes are the primary concern in system stability as they limit the power transfer capability in inter-region tie-lines. Therefore, to provide adequate damping to critical LFO modes, a robust wide-area damping controller (WADC) design is required. In this paper, time delayed feedback control (TDFC) based WADC design is carried out with large-scale solar photovoltaic (SPV). In the design process, geometric technique is used to determine the appropriate wide-area signals. Time delays and noises in feedback signals as well as different operating scenarios have severe implications on the damping performance of WADC. Hence, considering these uncertainties, the proposed WADC parameters are tuned by modified particle swarm optimization (PSO) algorithm. The performance of proposed WADC is demonstrated on SPV-integrated IEEE 4-machine 11-bus and 16-machine 68-bus systems. Critical modes of the system are damped by more than 10% damping ratio in both cases. Furthermore, nonlinear dynamic simulations demonstrate that the proposed WADC provides robust performance over wide operating scenarios. Finally, practical efficacy of the proposed method is established by experimental validation through real-time simulation using OPAL-RT.