Security Constrained Economic Dispatch Based on Shift Factor Adaptive Calculation

Security-constrained economic dispatch (SCED) is a dispatch plan for generating units that aim to achieve economic efficiency and safety developed by power system control centers. To meet the security and economic requirements of security-constrained economic dispatch, the market operator adjusts transmission line currents to satisfy security constraints and allocates adjusted surpluses or costs to maximize economic benefits when the transmission line load exceeds security constraints during safety verification. The sensitivity of branch currents to the injected power at each bus is defined as the shift factor of network security constraints. The sensitivity relationship between unit outputs and line loads could be derived by calculating the sensitivity coefficient matrix based on the line load direction matrix and the system conductivity matrix. Selecting an appropriate isolated shift factor is challenging yet crucial to achieving safe and constrained economic network operation. This paper analyzes transmission factor selection schemes: coefficient proportional screening and coefficient by screening. By comparing these schemes, the study aims to rationalize the selection of the isolated shift factor and achieve a safe and economically optimized network operation.