A preventive security constrained optimal power flow for mixed AC-HVDC-systems

摘要

At present, (N-1)-security of AC-HVDC-systems is evaluated separately for both the AC and HVDC grid. The application of Voltage Source Converters (VSCs) ensures a controlled power exchange between both systems. This enables a combined system operation and therefore a combined security consideration of both systems. This work proposes a Preventive Security Constrained Optimal Power Flow (PSCOPF) which adapts VSCs' set-points (p and u) in order to increase the overall system's security by minimizing the number of critical contingencies. AC- and HVDC-transmission lines outages are respected, thereby enabling a combined security analysis. The PSCOPF method is based on a Differential Evolution algorithm. To improve the computational effort, the impact of both the incorporated power flow algorithms and the contingency handling technique are investigated in detail.