Two Successive Approximate Models and Linear Formulations for Power Flow Analysis of DC Grid

DC distribution power system and DC Microgrid are becoming a reality, and the power flow analysis is crucial for the operations of DC power grid. This paper proposed two successive power flow models for DC grid based on admittance matrix (the node voltage method) and loop-analysis theory respectively. In addition, the related linear formulations via Taylor's series expansion have been also developed and they are consistent in nature with the iterative methods. The loop-analysis theory based method presents a new approach to get the resistance matrix. ZIP loads, V nodes and dispatchable distributed generators (DG) units are taken into account. Numerical results verify the accuracy and effectiveness of the proposed methods in comparison with the classical Newton–Raphson method and other exiting linear methods.