To increase the stability of power grid operation, the calculation method selected in this paper is the improved Newton-Raphson power flow calculation method, which is compared with the traditional Newton method and the forward-backward substitution method through MATLAB programming. The ETAP Power Station is used to calculate the voltage offset according to the bus voltage and branch loss in the power flow calculation results of the improved method. Calculate the amount and network loss, and calculate the short-circuit point current and short-circuit capacity through the short-circuit calculation, and verify the electrical equipment. The simulation results show that the improved method can reduce the calculation error and speed up the calculation. After the grid voltage is regulated by the reactive power compensation device, each voltage node keeps within its stable range, and the total active and reactive power losses of the grid are reduced resulting in a more stable operation performance of grid. Provide the basis for the correct selection of electrical equipment and the safe operation of the system.