Line Load Rate Characteristics

The source-grid-load coordination can be assessed from different perspectives. From the perspective of power grid security, the power flow distribution is the result of the interaction of the three, and it is also the main factor restricting the power balance. The previous studies show that when the power angle of the active power path is balanced the static security of the main grid is in the best condition, but that it is not easy to obtain the power angle path. Practical experience shows that the line active load rate balance of the main grid is generally positively correlated with the path power angle balance. The more balanced the path power angle is, the better static security of the main grid is. Therefore, the key is how to evaluate the line load ratio balance in the variable time window for the time-varying power flow distribution. Studies have found that after constructing the active load rate sequence matrix of the main grid line and performing the singular value decomposition on it, the main matrix contains the key information of the overall dynamic balance of the load rate, while the subordinate matrix contains the load rate timing characteristics of the uncoordinated line. As a result, according to the singular value and the left singular vectors, the overall balance index of the active load ratio are constructed, and the identification methods of the heavy load lines, the uncoordinated lines and the temporal feature difference are also proposed. For the three operating modes of the IEEE39 system, the analysis process is demonstrated and the feasibility of the proposed indicators and methods are verified, and the two-way verification is carried out with the quantitative index of main grid security proposed in the previous study. This research provides a practical method for the source-grid-load coordination evaluation based on big data, and presents the key information for the operation and planning of large power grids.