Decentralized Economic Dispatch Scheme With Online Power Reserve for Microgrids

Decentralized economic operation schemes have several advantages when compared with the traditional centralized management system for microgrids. Specifically, decentralized schemes are more flexible, less computationally intensive, and easier to implement without relying on communication infrastructure. Economic operation of existing decentralized schemes is also usually achieved by either tuning the droop characteristics of distributed generators (DGs) or prioritizing their dispatch order. For the latter, an earlier scheme has tried to prioritize the DG dispatch based on their no-load generation costs. Although the prioritization works well with some generation costs saved, its reliance on only the DG no-load generation costs does not allow it to operate well under certain conditions. This paper thus presents a more comprehensive economic dispatch scheme, which considers the DG generation costs, their power ratings, and other necessary constraints, before deciding the DG dispatch priorities and droop characteristics. The proposed scheme also allows online power reserve to be set and regulated within the microgrid. This, together with the generation cost saved, has been verified experimentally under different reserve, load, and DG conditions.