With the rapid development of China's power industry, the power grid structure tends to be complicated. In order to further optimize the grid structure, through the analysis of the actual grid, this paper proposed that the power grid had two functional attributes of hydropower transmission and load center. According to the characteristics of different functional attributes, a regional power grid planning method was proposed, which considered economy, hydropower transmission and load center functional attributes. It included objective functions and related constraints such as line construction cost, line operation cost, hydropower transmission profit, system blocking coefficient, and short-circuit current penalty function. MATLAB and PSD-BPA joint simulation method were used to analyze a regional power grid with high-attributed hydropower transmission and medium-attributed load center. The results show that the grid structure index of the optimization model considering the functional attribute is better, which can effectively promote the consumption of hydropower transmission and reduce the short-circuit current level of the load center.

The flexibility retrofit of thermal power has been proposed as a highlight in the 13th Five-Year Power plan, but the development trend during the 13th Five-Year Plan period in different regions is diverse. In the long run, thermal power, as the main body of China’s power generation capacity, will still provide the most important regulation capacity in most regions. Thus, this article comprehensively sorts out the domestic and foreign development history of flexibility retrofit of thermal power, summarizes the key technical, economic, and mechanism factors that affect its progress, proposes typical flexibility retrofit models, and discusses its future development prospects and key research issues. The investigation shows that, with the establishment of various flexibility markets, flexibility retrofit of thermal power in China will transit from policy-oriented to market-oriented, and flexibility will also become the core indicator of thermal power and even the entire power system from plan, design to operation. It will be an important cornerstone of the successful transformation for China’s power system building the technical standards and planning system with Chinese characteristics for thermal-power flexibility retrofit.