The iterative process of power flow calculation is a process from initial value to true value. You can refer to the iterative mathematical model of Niulafa. The change of line resistance is equivalent to the change of curve, and the number of iterations will change.

The term power flow calculation in electric power science refers to calculating the distribution of active power, reactive power and voltage in the power network under the conditions of given power system network topology, component parameters and power generation and load parameters. Power flow calculation is to determine the steady-state operation parameters of each part of the power system according to the parameters and operating conditions of the given power grid structure, generators, loads and other components. Usually, the given operating conditions include the power of each power supply and load point, the voltage of hub point, the voltage of equilibrium point and phase angle in the system. The operating state parameters to be solved include voltage amplitude and phase angle of each bus node, power distribution of each branch and power loss of the network.