Study on Power Supply Reliability of Sending End Matching Power Access to Ultra-high Voltage AC and DC Hybrid Power Grid

With the continuous operation of ultra-high voltage (UHV) AC and DC power transmission and transformation projects in Inner Mongolia autonomous region, Inner Mongolia power grid has become a UHV AC and DC hybrid system. However, the development of AC and DC projects is not balanced, and the characteristics of "strong DC and weak AC" are obvious, It is bound to affect the safe and stable operation of UHV power grids, when sending end matching thermal power units connecting to UHV AC and DC hybrid power grid, the reliability of power supply is difficult to be guaranteed. Taking the sending end regional power grid of Xilinhot to Taizhou (Jiangsu Province) UHV DC transmission project (hereinafter referred to as Xitai DC) as the research object, by using Power System Analysis Software Package simulation software, this paper deeply analyzes the influence of high-power matching power supply on the safe and stable operation of the power grid after connecting to the UHV AC and DC hybrid power grid, and put forward the corresponding prevention and control measures.