This paper aims to analyze the power flow of a gridconnected 11.4 kV high-voltage microgrid (MG) with various distributed resources (DRs). First, related papers and technological reports were extensively surveyed. Accordingly, five different types of DRs and their controllable loads were considered for integration into two 11.4 kV primary feeders. These DRs include two 1.5 MW diesel engine generators, two 1.79 MW gas turbine generators, two 1.0 MW fuel cell generation systems, a 1.5 MW wind turbine generator, and a 0.5 MW photovoltaic generation system. Second, using the Newton- Raphson method, we developed a sequential power flow program in Matlab environment and verified its accuracy. Finally, the program was used to simulate and analyze the power flow of an MG for one 24-hour period under the grid-connected operating mode. The outcomes of this paper should prove helpful for distributed engineers to further understand the behaviors and characteristics of high-voltage MGs.