Stability Assessment of a Three-Phase Grid-Tied PV Inverter with Eigenvalue-Based Method

This paper presents small-signal stability assessment of a grid-tied PV inverter system by using the eigenvalue-based method. A full-order state-space model is established considering controllers, grid synchronization, system delay and passive elements. The influences of different parameters on the system stability are analyzed by observing eigenvalue locus. The impact of different components on system stability is analyzed through participation analysis. Stability improvements through a better control design are discussed and validated.