Coordinated Restoration Control Method for Multi-DC Feed-in System Faults

Abstract

The invention discloses a coordinated recovery control method after multi-infeed direct current system failure, and belongs to the technical field of electrical power system running control. According to the method, a coordinated recovery strategy after system failure is used, incremental current recovery is conducted according to recovery strength of the multi-infeed direct current power of all direct current subsystems in the system, and during the calculation of the recovery strength of the multi-infeed direct current power, the transmission power of all the direct current subsystems, the strength of a multi-infeed receiving end alternating current system, the structure of a multi-infeed direct current system and the interaction of all the direct current subsystems are integrated into consideration. Accordingly, the transient stability of the system in the restoration stage after failure is effectively improved, and the possibility that subsequent commutation failure and even the system voltage destabilization occur in the restoration stage is greatly reduced.

Description

technical field [0001] The invention relates to the technical field of power system operation control, in particular to a coordinated recovery control method after a multi-DC feeding system fails. Background technique [0002] In recent years, with the large-scale construction of high-voltage direct current transmission projects in my country, the load center with large demand for electric energy has gradually formed a "multi-DC feed-in system" with multiple DC drop points. The multi-DC feed-in system can solve the problem of electric energy well. Long-distance transmission and power shortage problems, but the mixing of multiple DC and AC systems greatly increases the complexity of the grid structure and brings great challenges to the operation and control of the grid. The selection of the power recovery scheme of the system is one of the important issues in the stable operation of the power grid. [0003] Since the DC subsystems in the multi-DC feed-in system are closely rel...

AI Technical Summary

Problems solved by technology

However, the power ratio of this index is based on the maximum DC transmission power in the multi-infeed DC system, which cannot reflect the proportion of each DC circuit to the total DC transmission power, and cannot well reflect the importance of each DC circuit to the system; at the same time, it reflects The MIIF value of the multi-circuit DC interaction is an experimental value, the physical concept is not clear, and it cannot reflect the structure of the power grid. Therefore, there is a certain error in the impact of the DC restoration process on the system stability reflected by the index value. It is necessary to carry out the above indicators. optimization

Images