Abstract: The power system is a complex dynamic system.The power flow calculation is one of the most basic methods in the power system analysis.It plays a very important role in studying the operation mode of the power system and determining the power supply scheme in the planning of power grid.In this paper,the actual power distribution data are used to analyze the operating state of the power system,and the unknown parameters of the system are improved.,And the PSASP simulation is used to compare the parameters.Practice shows that the circuit reactance value is much larger than the resistance value of the system,you can use the tidal current distribution data to accurately calculate the system operating parameters of the components.