In response to the challenge posed by the high proportion of new energy intensity uncertainty within island microgrids
which can lead to significant frequency fluctuations and exceed the boundary threshold in extreme cases
thereby triggering the protective action of power grid devices and endangering the security and stability of the power grid
we propose a multi-source collaborative scheduling method for islanded microgrids. This method considers converter frequency support and capacity constraints. Firstly
a dynamic frequency response model for the islanded microgrid with multi-source participation(wind
photovoltaic
hydro
and storage)in dynamic frequency support is established.This model includes the system′s multi-source power-frequency time-domain expression and dynamic frequency safety constraints. Secondly
the relationship between the capacity limitations of converter and the demands for active frequency modulation and reactive voltage regulation is discussed.A dynamic frequency support strategy based on the remaining available capacity of inverters is proposed.With dual optimization objectives of system operational economy and frequency-voltage security
and considering constraints such as dynamic frequency and voltage safety
an optimal dispatch method for islanded microgrids is proposed
incorporating coordinated frequency and voltage regulation by wind
photovoltaic
hydro
and storage. Finally
simulation results based on an improved IEEE 33-node system validate the effectiveness of the proposed method in enhancing the frequency and voltage stability of islanded microgrids under large disturbances and uncertainties.