Three approaches to use Cross-Entropy in reliability evaluation of composite system with high peneration wind energy

With the rapid development of renewable energy, the future power system certainly contains a plenty of generators with random output. These uncertain factors usually will aggravate the difficulty of reliability evaluation. On the other hand, the renewable energy generator likes a single wind turbine usually has small capacity. A wind farm has a plenty of wind turbines. The enormous increase of system dimension due to the integration of a plenty of wind turbines will also causes the decrease of system reliability evaluation efficiency. Hence, a high efficient reliability evaluation algorithm aiming at the composite system with the high proportion of renewable energy should be developed. As far as we know, high computation efficiency is an eternal topic of power system reliability evaluation. Recently, a Cross Entropy-Importance Sampling (CE-IS) based reliability evaluation method has been developed successfully in the application to power system reliability evaluation. All cases verify that the method can improve the evaluation efficiency remarkably, especially in those highly reliable systems (i.e. cut-load events are rare events). This paper studies the approach to deal with the composite system reliability evaluation considering the integration of wind energy using Cross Entropy (CE) method, and proposes three different approaches to deal with the problem. Finally, a modified test system with the integration of renewable energy is proposed to compare the effects of these integration approaches.