Optimal Power Sharing of an Inverter-Based Autonomous Microgrid

Stability   of   the   autonomous   microgrids   while sharing the power between multiple distributed generation (DG) units is an important task. Conventional droop control is usually used for power sharing between DGs. Power sharing coefficients and controller parameters affect the stability of the microgrid. In this  paper,  to  improve  the  transient  dynamic  response  of  the microgrid,  a  power  derivative-integral  term  is  added  to  the conventional droop control. The design problem is formulated as an  optimization  problem.  The  power  sharing  coefficients  and controller  parameters  are  obtained  using  the  particle  swarm optimization  (PSO)  to  achieve  the  microgrid  stability  based  on power  error  minimization.  Nonlinear  time  domain  simulation is executed  to  investigate  the  proposed  controller  effectiveness  for different   disturbances.   Finally   the   results   show   satisfactory performance  with  efficient  transient  damping  characteristics  of the autonomous microgrid.