Analysis of Frequency Control in Microgrids with Multiple Phasor Measurement Unit Delays

In this paper, the small-signal stability of an islanded microgrid with multiple PMU communication delays is analyzed in terms of the secondary frequency control. A small-signal model is obtained for the microgrid. The relationship between the secondary frequency control gains and the PMU delays is investigated by using eigenvalue analysis. It is found that the feasible sets of secondary frequency control gains decrease as the maximum PMU delay increases. Time-domain simulations on the islanded microgrid have verified that multiple PMU delays can seriously affect the microgrid secondary frequency control.