Risk-oriented preventive control of transmission lines overload

Traditional preventive control strategies do not take into account the likelihood of each potential contingency, thus the dispatch results may often be conservative or radical. Aiming to achieve a reasonable tradeoff between economy and security, this paper develops a risk-oriented preventive control (ROPC) strategy. A three-state weather model is introduced to reflect the impact of weather conditions on the failure rate of transmission lines. Using the multi-objective optimization (MO) method, system security level associated with overload risk can be controlled in advance. A distance based multi-objective particle optimization (DSMOPSO) algorithm is adopted to solve the MO problem. Simulation results obtained on a six-bus system are analyzed in comparison with OPF and PSCOPF to show that the proposed ROPC could provide a useful decision-making tool to keep an optimal balance between system operational cost and overload risk in different weather conditions.