Research on Coordination Solution Strategy of Power System Transient Stability and Short Circuit Current Based on External Penalty Function Method

As large-capacity units shift down to low-level power grids, the problems of transient stability and short-circuit current of power systems become increasingly prominent. The traditional control methods such as generator-tripping and load-shedding can only solve one of the problems, but cannot fundamentally solve the contradiction between transient stability and short-circuit current at the same time, resulting in poor power grid stability. A practical control strategy of connecting transient stability and short-circuit current problems of the system through system impedance are studied for the first time in this paper and a mathematical model is established with system impedance as the core. An external penalty function method is proposed to solve the contradiction between transient stability and short-circuit current by seeking the optimal impedance of the system. Taking GGE (A power grid in Hubei) regional power grid as an example for simulation verification through Power System Analysis Software Package (PSASP), the results show that the problems of transient stability and short-circuit current in the GGE regional power grid have been effectively solved and the power grid can operate stably. It is verified that the proposed coordinated control strategy of transient stability and short-circuit current can effectively improve the stability of power system.