Resilience-Oriented D-PMU Based Frequency Controller for Islanded Microgrids With Flexible Resources Support

Abstract

This paper proposes a novel frequency regulation outlook focused on the improvement of islanded microgrids resilience. The proposed method takes advantage of power systems enhanced situation awareness enabled by distribution-level phasor measurement units (D-PMUs) monitoring to overcome current design boundaries that limit an effective harnessing of flexible resources potential to support microgrids resilience. For this, capitalizing on D-PMUs high resolution, low latency and time synchronized measurements, a beforehand assessment of the power mismatch leading the microgrid to frequency nadir condition is achievable during the early stages of the system dynamics. Based on this information, new measurement-based control modules are designed to address individual stages of the frequency regulation process in a dedicated manner, respectively arrest, rebound and recovery stages. These controllers provide a significant improvement of microgrid's frequency arrest and rebound ability, while ensuring a smooth recovery process toward the system steady-state realization. The proposed approach stability is mathematically demonstrated and comparative case-studies developed considering monitoring and communication systems non-idealities. Obtained results indicate the proposed controller superior ability to address single and cascade large-scale disturbances, while simultaneously providing an improved frequency regulation performance and greater economic benefit for flexible resource support.