Design of a controller for active power sharing in a highly-resistive microgrid

This paper presents a new control algorithm for active load sharing in a highly-resistive inverter-connected microgrid under different loading conditions. A systematic procedure for modifying the conventional droop control approach, regarded as reverse droop control, is presented in this paper. The gains of the proposed controller are selected based on the eigenvalues obtained from linear modal analysis. The linearized microgrid model is further analyzed to develop a mathematical expression for sharing active power. The proposed accurate successive approximation among line parameters, load and control gains gives equal power sharing among distributed generators without any communication. The performance of the proposed control methodology is verified on a low voltage (LV) test microgrid by applying severe faults, including load change scenario and disconnection of one DG unit. It is clearly observed from case studies that the proposed control scheme is effective to stabilize this kind of microgrids and provides excellent power sharing performance in islanded mode.