Voltage and Power Balance Improvement in Bipolar DC-Microgrids Using Feedback Linearization ethod

Abstract

The bipolar DC microgrid connects resources and loads at three different voltage levels, and it has a higher reliability and efficiency than conventional DC microgrids. However, the power imbalance in this type of microgrids may lead to several challenges including unbalanced load distribution among sources, voltage imbalance in positive and negative poles, power quality issues, and non-optimal operation of the system. This issue is targeted in this paper, and using a buck-boost balancer is tried to mitigate the problem. To this end, the state space model of the bipolar DC microgrid and the voltage balancer converter is extracted, and considering its nonlinear dynamic, the feedback linearization technique is applied to improve the voltage and power balance. Finally, the effectiveness of the proposed method is verified through simulation in MATLAB/SIMULINK software taking into account different conditions and the presence of uncertainty in the system parameters.