A new relaxation method to obtain reactive power allocation in regional power grid

This paper analyzes the problem of reactive power optimization (RPO) in regional power system thoroughly. Successively, we further discuss the problem caused by the mismatch of the configuration of reactive power compensation and the demand of the system. Eventually an extreme optimal power flow method (EOPF) is proposed to verify the validity of the existing reactive power compensation. By relaxing the control variables including the range of transformer taps and the capacity of capacitors, the proposed method enlarges the convergence region of the optimization algorithm and further provides the advice of optimal allocation of reactive power compensators for departments of system planning and operation. Case study on a regional power grid with load uncertainty in Sichuan Province, China demonstrates the effectiveness of the proposed EOPF method.