Overload security and risk assessment of overhead lines

The paper presents a new approach to assess the risk associated with overload of transmission lines for the purpose of power system planning and operation management. In electrical systems, one of the main factors that limit the transport of energy is the temperature of the conductor. Knowing the transmission system, and the critical sections both geographical and climatic, the temperature of the line as well as the transient thermal rating can be calculated. A plot of the allowable safe operation time under transient conditions allows increase in transmission capacity without compromising operational security. The estimate of probabilistic thermal risk can afford significant advantage making economic dispatch during favorable conditions without violating the maximum temperature of the transmission lines. This information will be useful in operational decision making and ultimately help to improve the reliability of the power system.