Reliability Evaluation of 500kV Terminal Station Considering Comprehensive Effect of the Grid and Station

摘要

As a significant part of reasonable grid, 500kV terminal substation has received extensive attention in recent years. In this paper, an engineering reliability evaluation algorithm for 500kV terminal substation is proposed. The algorithm divides the 500kV terminal substation into three parts which are 500kV tielines, main connection within the substation, and 220kV power grid to evaluate the reliability of 500kV terminal substation. With markov model (MM), the whole tache reliability analysis has been introduced, including reliability analysis model, method, and indices system. Based on root cause analysis (RCA), the affecting factors are then analyzed, which includes 500kV tielines, substation buses' type, together with 220kV grid's structure, power source distribution and load distribution. At last, a certain 500kV substation which is rebuilt to terminal substation in Guangdong grid is analyzed as an example using the reliability evaluation algorithm, which verifies the practicality of the algorithm. The results show that the reliability of 500kV hub substation decreases to some degree when modified to terminal substation. Reasonable 500kV terminal substation can insure the reliability to a level which satisfies the demand of engineering application. 500kV tielines and substation buses' types are main factors which affects the 500kV terminal substation's reliability.