Dispatchable Microgrids: An Extended Provision of Systemic Ancillary Services to Low-Voltage Distribution Grids

Grid-connected advanced microgrids are controllable entities that can actively interact with low-voltage distribution systems, becoming demand response providers and dispatchers of ancillary services. However, in general, microgrids' management strategies only exploit a limited portion of their potential for ancillary services provision, being usually designed case-by-case to target one particular application. This paper presents an extended outlook on systemic ancillary services that can be provided by an advanced microgrid comprising bidirectional power controllability at its point-of-common-coupling. It is demonstrated that the microgrid operation can be shaped according to several electrical principles (e.g., resistive, capacitive, inductive, voltage-controlled behaviors, etc.), allowing the upstream low-voltage distribution grid to benefit from these particular functionalities. In addition, this paper discusses several fundamental aspects required to fully exploit the capability to provide such an extended range of ancillary services by microgrids. It also discusses the needed control and physical infrastructures, as well as their expected market-related interactivity. Experimental results carried out on two different low-voltage microgrid prototypes are presented to demonstrate that the offering of such multiple ancillary services can be implemented in real-life applications.