Paper Sharing: Stability Analysis of a Direct-Synchronized Single-Phase Grid-Tied Inverter

We are pleased to introduce the paper “Stability Analysis of a Direct-synchronized Single-phase Grid-tied Inverter” written by R. Agrawal, B.P. McGrath, C.A Teixeira, and R.H. Wilkinson from RMIT University.

The paper was presented at the 2023 IEEE 8th Southern Power Electronics Conference and 17th Brazilian Power Electronics Conference (SPEC/COBEP).

Know more about this paper:

https://ieeexplore.ieee.org/abstract/document/10408509 

Brief Introduction:

The paper analyzes the stability of a single-phase voltage source inverter (VSI) system by evaluating two direct synchronization methods employed in its phase-locked-loop (PLL): (1) by using the capacitor voltage and second-order generalized integrator (SOGI) quadrature output as PLL input, (2) by directly using both SOGI outputs as PLL inputs. A synchronous reference frame small-signal model is developed by introducing fictitious orthogonal quantities, and Floquet theory is applied to analyze the stability. Validation includes DSIM co-simulation and experimental testing with a 5-kW grid-tied inverter.

Verify the stability analysis and predictions of the Voltage Source Inverter (VSI) system using DSIM co-simulation

In this paper, DSIM is used to replicate the experimental setup of the 5 kW VSI system and simulate the system's behavior, comparing it with analytical predictions derived from mathematical models such as matrix eigenvalue analysis. Furthermore, DSIM co-simulation results validate practical data including capacitor voltage, inverter output current, PLL frequency, and phase.