System Reliability and Fault Tree Analysis of SeSHRS-Based Augmentation of Hydrogen: Dedicated for Combined Cycle Power Plants

This paper presents a seven-stage hot redundant structure (SeSHRS)-hydrogen cooling system (HCS), dedicated for cooling of 2 x 660 MW size generators of combined cycle power plants. In the case of large generators, air cooling system restricts itself up to 100 MW generation capacities, while HCS is very effective as a coolant for capacity of 120-130 MW unit(s) and above. To control and monitor such a critical system, it is essential to incorporate supervisory control and data acquisition with HCS for effective cooling of the large generators, and taking proactive actions, if abnormality is observed during the operation. The objectives of this paper are to analyze the system reliability and system failure of the proposed process control and instrumentation of HCS. The work includes a comparison between the proposed and the existing systems in terms of system reliability and fault tree analysis (FTA). The algorithms for system reliability and FTA of the proposed SeSHRS model are developed on the MATLAB platform. The effectiveness of real-time featured proposed HCS is validated by computer simulation. The entire process instrumentation of the system is designed and simulated on RSView Studio, a real-time automation platform by Rockwell Automation, Milwaukee, WI. The proposed design meets the specifications of IEC 61025, IEEE C37.1-2007, and IEEE 1413-2003.