Continuous Stability Monitoring of DC Microgrids Using Controlled Injection

Emerging dc microgrids incorporating energy storage are presenting new challenges in system design and stability analysis. Several methods have been proposed in literature for online stability evaluation of such dc microgrids using impedance-based stability analysis. This paper presents a method for continuous monitoring of system stability that is not computationally intensive and can be added as a supplemental function to existing converters in the system so that no additional power hardware is required. The proposed method evaluates stability continuously and can be used as a proactive approach for monitoring and maintaining system stability. Hardware results are presented to validate the proposed continuous stability monitor, which shows its effectiveness in predicting the system stability margins.