Aspects and embodiments described herein are directed to power interface devices and methods. In one aspect, a method for controlling a microgrid is provided. The microgrid includes a power interface device coupled to one or more microgrid elements comprising power sources and loads. The method includes determining, by the power interface device, a mode of operation of the microgrid, determining a power load of the one or more microgrid elements, and based on the mode of operation of the microgrid and the power load of the one or more microgrid elements, adjusting, by the power interface device, a frequency of a voltage of the power interface device to control the one or more microgrid elements.