Optimisation of Motor Loads in Short-Circuit Current Calculation

Short-circuit current calculation is the basis of power system planning, development and protection. In power system simulation calculations, the load model is connected directly to the substation high-voltage bus. However, the actual load is generally connected to the grid via the distribution network, which is not taken into account in existing short-circuit current calculations. Based on the analysis of the influencing factors of short-circuit current, this paper puts forward a method to determine the proportion of induction motors connected to the short-circuit bus or other non-short-circuit buses when calculating the short-circuit current of 110 kV and above voltage level buses, and uses PSASP to simulate and analyze a network system with distribution network of different voltage levels that conforms to the load distribution characteristics of a province's power grid, in order to improve the accuracy of short-circuit current calculation results of power system.