Fuzzy based Intelligent Power Sharing Control Scheme for Hybrid Microgrid

Despite, the environmental and technical benefits, uncertainty and intermittency are the main challenges in implementing the renewable energy sources (RES).Therefore, integration of a cluster of RES based Distributed Generation (DG) into a coordinated and controlled Microgrid (MG) system is a viable solution to address those concerns.Moreover, to optimize the advantage of the MG system, the combinations of AC and DC DG unit into a Hybrid Microgrid (HMG) architecture can be considered.Operation of several AC and DC DG units within HMG should be precisely controlled and monitored in term of a robust power sharing control to provide a reliable power supply for the load.Conventionally, the droop control method with fixed droop control parameters has been widely used to support the power allocation scheme within MG.The fixed droop control strategy leads to some limitations such as inflexibility, poor of voltage regulation and dynamic responses when the HMG is operated under fluctuating circumstances.The paper presents an intelligent power sharing control strategy designed to proportionally control the contribution of each DG unit within HMG.Fuzzy Logic Control (FLC) control algorithm is implemented to provide a coordination control between ACMG and DCMG within HMG.The proposed control framework dynamically adjusts the droop control parameters and controls the power contribution among DG units under uncertain conditions of RES and load demand.It has been monitored that the proposed intelligent control provides enhancements of HMG frequency and voltage dynamic performances.Under transient and load change events, the frequency response improved as indicated by higher frequency nadir and lower frequency deviation.More damped oscillatory condition of frequency and voltage dynamic performances are observed, providing improvement of HMG frequency and voltage stability.More proportional and equal power allocation among DG unit is monitored, mitigating the risk of circulating current among DG units and ensure reliable and efficient operation of HMG.It has been monitored that the system efficiency improves by 2,77%, providing enhancement of voltage regulations and eventually increased system loadability without violating the voltage stability margin.