Design-Oriented Large-Signal Stability Analysis of Synchronous Reference Frame Phase-Locked Loop

The Synchronous Reference Frame Phase-Locked Loop is a central component of grid-following Voltage Source Converters. Previous research has shown that the differential equation introduced by this loop is a swing equation, similar to that of the synchronous machine. This paper analyzes the large-signal stability of a single converter connected to an infinite-bus system. The outcome is a boundary in the plane of the parameters separating a region of insufficient damping and a region of sufficient damping. Moreover, the boundaries of stability from the small-signal analysis are also included for completeness. The findings are validated via time-domain simulation in EMT models.