Instability caused by low inertia and constant power loads is a major challenge of DC distribution grids. Previous research uses oversimplified models or does not provide general rules for stability. Therefore, a comprehensive approach to analyze the stability of DC distribution systems is desired. This paper presents a method to algebraically analyze the stability of any DC distribution system through the eigenvalues of its state-space matrices. Furthermore, using this method, requirements are found for the stability of three example systems. Additionally, a sensitivity analysis is performed, which considers the effect of several system parameters on the stability and disputes some overgeneralized conclusions of previous research. Moreover, various simulations are performed to illustrate the dynamic behavior of a stable and an unstable DC distribution system.
- DC distribution
- sensitivity analysis