Scheduling Model for Inter-regional HVDC Tie-line Generation and Transmission System Considering Conditional Sections

The HVDC transmission schedule for clean energy seldom considers the demand of receiving grid. With the expansion of clean energy scale, it brings great pressure to the receiving grid for safe and stable operation. For this reason, a generation and transmission scheduling model of inter-regional HVDC tie-line system considering conditional section is proposed. A step power adjustment model for the HVDC tie-line operation optimization is developed with consideration given to various constraints on tie-line power, which not only give full play to the characteristics of HVDC tie-line that can be flexibly adjusted, but also avoid the frequent conversion of HVDC converter equipment, making the HVDC tie-line schedule more executable. The joint operation model of cascaded hydropower plants in sending grid is established to meet the operational constraints such as the restricted operating zones of hydropower units, and to ensure the priority of clean hydropower resources and the practicability of the hydropower schedule. The model of conditional control section is established, which can effectively deal with the problem of the coupling between the power limits of section and the number of running units, so as to ensure the safe and stable operation of related sections. Based on the actual data of a cross-regional interconnected power grid, the validity of the model is verified, which can promote the accommodation of clean energy across a wide range of regions, reduce the supply cost of large power system, and alleviate the pressure of safe and stable operation at the receiving system.