Research Projects

High levels of renewable penetration are transforming power-swing phenomena: what was once dominated by the system’s physical inertia is now increasingly dictated by inverter-controller dynamics. This project explores how the grid-forming (GFM) and grid-following (GFL) controller parameters reshape the impedance trajectory that distance relays ‘see’ during power swing and how protection relays can be adaptively set accordingly. The objectives of the project include, i. Developing a standard test system to assess the impact of IBR penetration on the grid during a power swing scenario. ii. Evaluating distance relay performance with IBRs using multiple control strategies (GFL/GFM). iii. Developing a power swing detection technique that is adaptive to IBR penetration. iv. Evaluate the performance of the devised system in simulation and on commercial hardware relay. Detailed EMT models (PSCAD/EMT-type) of the IEEE-9-bus system will be modified to include GFM and GFL sources. Multiple case studies will be simulated to arrive at an in-depth understanding of the impact of controller parameters. The hypothesis is that (a) PLL bandwidth, (b) dc-link voltage controller parameters in the case of GFL and (a) voltage reference current generation controller parameters, including virtual-inertia time constant and droop gain, and (b) types of current limiters for GFMs govern both the shape and speed of the impedance trajectory. This hypothesis needs to be established theoretically and based on simulation. Sensitivity analysis can be done based on parametric sweep to establish the participation of different parameters during power swing. Adaptive power swing detection principle can be developed once the trivial parameters that affect the power swing phenomenon are identified. Performance of the devised principle can be tested in simulation and on commercial hardware relay to prove its effectiveness. Achieving these goals would result in the systematic, quantitatively confirmed relationship between inverter-control parameters and relay settings, allowing utilities to maintain dependable protection settings as the converter penetration is ramped up to above 50% of installed capacity.