Conservation Voltage Reduction for Autonomous Microgrids Based on V–I Droop Characteristics

Conventional droop characteristics for microgrids have been primarily proposed to achieve proper load sharing between the various distributed generation units. This paper proposes a different perspective for designing autonomous microgrids, which aims at reducing the power consumption of the microgrid by utilizing the concept of conservation voltage reduction. The proposed control strategy relies on a voltage–current (V–I ) droop characteristic, designed to perform demand side management through voltage control. The effectiveness of the proposed control scheme is demonstrated through time-domain simulation studies considering voltage dependent loads tested over a range of loading conditions and power factors. The performance of the proposed scheme is compared to the conventional and adaptive P-f/Q-V decentralized droop control. Further, a comparison of the transient analysis of the three droop schemes in case of a fault has been evaluated. The proposed V–I droop control scheme can maximize the number of loads being supplied during power shortage.

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