This paper presents new proposed fully-distributed cooperative control for a microgrid to work autonomously with high renewable energy penetration. For a microgrid to work autonomously, it must maintain its own supply-demand balance in term of active power and regulate the system frequency and voltage magnitudes. As the Distributed Generators within a microgrid could be diverse and distributed, the control and management solutions should be as efficient and cost-effective as possible for the microgrid to be economically viable. Since well-designed distributed control solutions can be flexible, reliable, scalable, and low-cost to implement thus they are promising choice for the control and operation of microgrids. As the popular maximum peak power tracking (MPPT) algorithms emphasize high energy usage efficiency but may cause a supply-demand imbalance when the maximum available renewable generations are more than demanded, especially for autonomous micro-grids. To maintain supply and demand, energy storage devices are used, however its effectiveness is also limited. presently conventional droop control is one of the most popular decentralized methods for sharing active and reactive loads among the distributed generators. However this method have several drawbacks, such as voltage and frequency deviations, inaccurate power sharing, and unsatisfactory transient performances. To overcome these problems, this paper proposes a distributed subgradient-based solution to coordinate the operations of different types of distributed renewable generators in a microgrid. By controlling the utilization levels of renewable generators, the supply-demand balance can be well maintained and the system dynamic performance can be significantly improved. Simulation results demonstrate the effectiveness of the proposed control solution.

V.Srinivasulu,M Madhusudhan Reddy."Proposed Subgradient-Based Solution for Coordination of Distributed Energy Resources in a Microgrid". International Journal of Computer Engineering In Research Trends (IJCERT) ,ISSN:2349-7084 ,Vol.2, Issue 07,pp.425-436, July - 2015, URL :https://ijcert.org/ems/ijcert_papers/V2I703.pdf,

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