Fault tolerance in a distributed control system for combined cycle power plants

This paper presents how a Fault Tolerant Scheme FTS for the controllers of a distributed control system is selected. A dual-redundant configuration was chosen based on a dependability analysis. The defined FTS is described in terms of the four phases of fault-tolerance. A combination of stand-by and a synchronous scheme is considered. The FTS resulted in a cost-effective solution in order to increase the control system reliability because two main reasons: the hardware configuration do not require special elements, and the FTS takes advantage of the manual tracking algorithm to make the FTS software simple. The FTS was implemented and is operating in various controllers of a distributed control system in a combined cycle power plant in Mexico.