  Optimal power flow (OPF) is an important technique for power systems to
achieve optimal operation while satisfying multiple constraints. The
traditional OPF are mostly centralized methods which are executed in the
centralized control center. This paper introduces a totally Distributed DC
Optimal Power Flow (DDCOPF) method for future power systems which have more and
more distributed generators. The proposed method is based on the Distributed
Economic Dispatch (DED) method and the Distributed State Estimation (DSE)
method. In this proposed scheme, the DED method is used to achieve the optimal
power dispatch with the lowest cost, and the DSE method provides power flow
information of the power system to the proposed DDCOPF algorithm. In the
proposed method, the Auto-Regressive (AR) model is used to predict the load
variation so that the proposed algorithm can prevent overflow. In addition, a
method called constraint algorithm is developed to correct the results of DED
with the proposed correction algorithm and penalty term so that the constraints
for the power system will not be violated. Different from existing research,
the proposed method is completely distributed without need for any centralized
facility.
