Study on the Influence of Large-scale New Energy Connect to the Operation Characteristics of Ultra-high Voltage Sending end Network with Weak Synchronization Support

In recent years, new energy sources such as wind power and photovoltaic have entered a period of rapid development at home and abroad. The unbalanced distribution of energy and load determines the main characteristics of large-scale development and centralized delivery of new energy in China. Therefore, large capacity and long-distance UHV transmission technology has become an important carrier of intensive and efficient development and large-scale allocation and consumption of clean energy. However, due to its characteristics of weak inertia, large output fluctuation and poor reactive power support, new energy seriously affects the safe and stable operation of the power grid, especially for the sending end grid with weak synchronization support, the large-scale access of new energy will have a inestimable impact on the transmission capacity and operation characteristics of UHV, and the reliability of power supply is difficult to be guaranteed. In this paper, PSASP (power system analysis software package) simulation software is used to study the transmission end power grid of Ximeng UHV AC / DC transmission project, the simulation analysis of the system strength, stability level, power transmission capacity and other operation characteristics of the power grid in the region after the planned new energy access is carried out, the impact of large-scale new energy on the safe and stable operation of UHV AC-DC hybrid power grid is analyzed in depth, and the corresponding effective prevention and control measures are proposed.