This project belongs to the field of power systems and automation.
In view of the increasingly prominent characteristics of the UHV power grid in East China Power Grid, the interactive effects of AC and DC have intensified, and the safety and stability characteristics of the power grid have become complex. Existing electromechanical transient simulation methods can no longer meet the simulation needs of accurately simulating DC response characteristics. This project focuses on the actual needs of the development of UHV AC and DC hybrid power grids, forms a systematic research framework, and establishes a detailed DC full-process model based on the actual DC control and protection system. The electromagnetic transient simulation platform and the electromechanical transient simulation platform for large AC and DC power grids provide technical means to grasp the characteristics of AC and DC interactions in the power grid. Using multiple simulation platforms, the characteristics of East China Power Grid are deeply studied from multiple dimensions such as transient stability, voltage security, and small disturbance stability. Aiming at the potential risks of the power grid, a control strategy for three defense lines of the power grid is formulated. Control technologies to prevent DC commutation failure and improve DC recovery capabilities are proposed from the DC body side and the power grid side, and research is carried out on issues such as peak regulation and frequency modulation, backup arrangements, and DC acceptance capabilities of the system after large-scale access of UHV DC. It effectively supports the smooth operation of actual UHV AC and DC projects and provides technical guarantee for the safe and stable operation of UHV AC and DC hybrid power grids.
This project has achieved fruitful research results in electromagnetic transient modeling technology, UHV DC quasi-steady modeling method and ability to withstand DC commutation failure of UHV AC and DC hybrid power grids, providing technical support for simulation analysis and operation control of large power grids. The project results have been applied in East China and relevant provincial power grids, ensuring the safe and stable operation of East China's UHV AC and DC hybrid power grids. It also provides technical guarantee for the smooth operation of Binjin Special HV DC and Zhejiang Ford HV AC projects. The results of the project will help improve the depth and breadth of understanding of the safe and stable operation of UHV AC and DC hybrid power grids, and allow us to have a deeper understanding of different forms of UHV power grids, their operating characteristics and potential safety risks. The research results of this project have good reference and promotion value for the safe and stable operation analysis and control of similar forms of power grids.
During the implementation of the project, 11 related papers were published, 6 invention patents were applied for, and 1 software copyright was obtained. The appraisal expert committee headed by Academician Wang Xifan unanimously believes that the research results of the project are generally at the international advanced level, including the electromagnetic transient modeling technology applied to the study of UHV AC and DC interactions, the UHV DC quasi-steady-state modeling method and the DC control and maintenance parameter optimization method to improve DC's ability to withstand commutation failure is at the international leading level.