Constant power flow control of point of common coupling for high proportion photovoltaic microgird

As a great deal of distributed generation relied on natural condition is introduced into utility grid, it may bring utility grid some adverse impacts. A constant power flow control strategy at point of common coupling (PCC) of microgird is presented in this paper to greatly decrease the negative impacts. It is pointed out that the target for power flow control of PCC is to keep the power flow at PCC around some constant. The objective function for controller design is to minimize both the cumulant error of power flow and the maximum power flow error at PCC. The objective function and a kind of new particle swarm optimization (PSO), named nonlinear diffusion particle swarm optimization (NDPSO), are brought forward as well. Taking a photovoltaic (PV) microgird in which the PV proportion is 50% for an example, the control parameters are optimized by NDPSO based on the objective function presented above. A simulation platform for grid-connected PV microgird is constructed in MATLAB/ SIMULINK and the simulation results show that the method is efficient.