Abstract
Conference Title: 2018 North American Power Symposium (NAPS) Conference Start Date: 2018, Sept. 9 Conference End Date: 2018, Sept. 11 Conference Location: Fargo, ND, USA This paper addresses the small-signal stability analysis of inverter-based microgrids when operating in islanded mode. The dc dynamics of droop-controlled inverters are taken into consideration revealing new small-signal stability requirements that were not investigated before. First, a linearized state-space model of a previously developed non-linear system is formulated. The traces of the eigenvalues of the linearized system are compared to traces of previous models to demonstrate how the dc dynamics of the inverters affects the stability of the system. Time-domain simulations of a microgrid are performed in MATLAB to test the validity of the results of the linearized model. Results point to a direct relation between the minimum values of the dc voltage source and the microgrid load to maintain system stability.