A SCADA system reliability evaluation considering performance requirement

Various types of supervisory control and data acquisition (SCADA) system have been implemented by the utilities around the world to provide and maintain the high level of confidence demanded for power system operation. One of the main concerns in the design of a SCADA system is to assure whether the system could fit with the reliability and performance requirements specification. To take the system performance into account in the reliability analysis of the SCADA system, an approach to the reliability and performance analyses is proposed in this paper. This approach is based on a model for evaluating data transmission time, which allows us to find the operation time needed to complete SCADA functions. With information on performance, the reliability evaluation technique using fault tree analysis (FTA) is described and applied for analysis of SCADA system component connectivity to assess the availability of SCADA controls. A sensitivity analysis is also described and used to illustrate the effects of input data uncertainty on the system reliability.