Optimal voltage control and loss reduction in microgrid by active and reactive power generation

This study suggests a new algorithm based on a combination of fuzzy logic and genetic algorithm (GA) to improve voltage profile and reduce loss in a microgrid. Considered microgrid includes control variables such as onload tap changer (OLTC), active power output of distributed generators (DG) and reactive power output of feeder switched capacitors that are controlled in a microgrid controller (MGC) through communication links. The proposed method was used to obtain the optimum value of control variables to reduce the loss and improve the voltage profile. The problem formulations consider three distinct objectives related to cost of loss, cost of injected active power by infinity bus and cost of injected active power by DG. The novel formulation is a multi-objective and non-differentiable optimization problem. The control variables were changed base on fuzzy logic and the GA was employed for finding the optimum shape of membership functions. In order to verify the proposed method, a 34 bus microgrid was analyzed in varying load condition and was compared with previous works. Finally it has been tested on 33-buses system to be investigated the control variables status, cost function status and voltage fluctuation during one day.