An Analytical Calculation Method for Total Transfer Capability of Transmission Section Based on Evaluation of System Short Circuit Capability

In the HVDC sending-end system, the system's short-circuit capacity is mainly provided by conventional generating units. When the operating mode of conventional generating units changes and the short-circuit capacity changes, it will have a significant impact on the system's safety and stability characteristics. The existing section total transfer capability calculation methods often ignore the key variable of short-circuit capacity when verifying the system's safety and stability, which may lead to calculation errors. Therefore, this paper proposes a section total transfer capability analytical calculation method based on short-circuit capacity evaluation. Firstly, the system security and stability constraints considering the short-circuit capacity are constructed. Then, the contribution index of conventional generating units to the system's short-circuit capacity is proposed, and a section total transfer capability analytical calculation method is proposed based on this index. Finally, taking a certain power grid in Northwest China as an example, the effectiveness of this method is verified through case analysis in the power system analysis and simulation program.