Integrated control system for

To get good control of the entire PRT, not only should the expander be controlled, but a completely integrated control system for this application should be designed. Most conventional control systems consist of individual control loops that only consider their specific tasks. The PRT—from a control perspective—is a multivariable system that requires integration between the different control loops. Further, some of the disturbances on the PRT are so fast that closed-loop control is too slow to keep the train under control. 

SIS, that is, additional problems introduced by SIS. In modem times for floating oil installations people go for a dynamic positioning (DP) system, in place of conventional mooring system. DP systems are independent systems, but needs to interact with integrated control systems for exchange of many data. Therefore, it is needless to tell assessment of reliability of the system is extremely important. Now, if there is some interface problem between the two systems, then additional complications will arise are they not Also at times, spurious actions from SIS make operators very much disturbed. In addition to the possible safety hazards, the SIS may also spuriously operate to disturb production and lead to losses and costs. Therefore, importance for assessment of reliability of SIS cannot be overestimated. There are several methods to assess reliability of SIS such as RED, FTA, LOPA, and risk graph. RED, FTA, and LOPA have already been discussed, so let s concentrate on risk graph now. 

The problems associated with carrying out the refuelling operation require a high Integrity control system for their solution. The two key criteria for such a control system are (a) safety and (b) system availability. The safety aspects cover areas such as prevention of radioactive release and plant damage whereas system availability Includes reduction of downtime and hence reduction In lost revenue due to the refuelling shutdown. 

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