Reliability Evaluation in Substations Considering Operating Conditions and Failure Modes.pdf

IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 27, NO. 1, JANUARY 2012 309 Reliability Evaluation in Substations Considering Operating Conditions and Failure Modes Dong-Li Duan, Xiao-Yue Wu, and Hong-Zhong Deng Abstract—A novel algorithm considering the operation con- kinds of weather was proposed by Billinton in [5]. The model ditions and failure types is proposed to evaluate the substation can reflect the impact of the weather changing frequency and reliability. As some devices’ outage probabilities vary with their duration on the component’s reliability, but the system state operation conditions, such as preventive maintenance measures space increases sharply with the numbers of components. The and external weather and internal aging conditions, a time-varying failure-rate model is presented first. In order to deduce the failure step function [6], exponential distribution function [7], as well events of the system, including passive failures, active failures, as the Weibull distribution function [8] were used to describe breaker stuck conditions, and overlapping failures, a substation the component’s aging and degenerating process in reliability. zone graph is created, and with the minimal cutsets from the zone Section II establishes a novel failure-rate model considering the graph to complete the failure events, the bus scheme reliability factors of weather, preventive maintenance and aging process calculation model is proposed. Applying the model and algorithm based on the multi-Weibull distribution function. to evaluate some substation systems, the results show that