A robust nonlinear stabilizer as a controller for improving transient stability in micro-grids.

Area of Science:

• Electrical Engineering
• Control Systems
• Power Systems

Background:

• Micro-grids (MGs) require robust control strategies for stable operation during various modes and transitions.
• Electronically-interfaced distributed resources (EI-DRs) are key components in modern MGs, necessitating effective stabilization techniques.
• Transient stability is crucial for MGs, especially concerning frequency deviations during operational changes.

Purpose of the Study:

• To design and validate a parametric-Lyapunov stabilizer for improving micro-grid transient stability.
• To develop a unified control configuration for EI-DRs applicable across grid-connected, islanded, and transition modes.
• To ensure the stabilizer's effectiveness, robustness, and implementation simplicity.

Main Methods:

• A parametric-Lyapunov approach is employed for stabilizer design.
• A novel parametric-Lyapunov function is introduced to enhance damping of transition transients.
• The stabilizer is designed to operate using only local information, eliminating communication link requirements.
• Mathematical proofs and time-domain simulations are used for verification and analysis.

Main Results:

• The proposed stabilizer demonstrates improved damping of system transition transients.
• Robustness of the stabilizer is verified through simulations and mathematical analysis.
• An ultimate bound for frequency transition transients is derived.
• The stabilizer's effectiveness is validated on a multi-resource MG and compared to existing methods.

Conclusions:

• The parametric-Lyapunov stabilizer offers an effective and simple solution for enhancing micro-grid transient stability.
• The stabilizer's reliance on local information and unified control configuration simplifies implementation and enhances applicability.
• The proposed method provides a robust approach to managing frequency transients and resource delays in MGs.