Standard Technical Features of BTG System for Supercritical 660 ...

Standard Technical Features of BTG System for Supercritical 660/800 MW Thermal Unitsb) Stream concept shall be maintained. The different equipment shallbe clubbed in such a manner that failure of a controller set affectsonly one stream of the process path, e.g. in air and flue gas path, IDfanA, FD-fan A, and rotary air pre heater– A can be clubbed onone set of controllers.c) Inter-related controls shall be provided in one group, i.e. when theloop /sequence of one equipment depends on the availability ofanother sequence /loop or equipment than these controls shall bepreferably be clubbed together e.g. PA fan controls depend on theavailability of mills/mill control, so, control of half the number ofmills can be clubbed with control of the relevant PA fan.d) While formulating the controller groups, it shall be ensured that thefailure of one function does not jeopardize the plant operation orcause shut down. For example if 6 mills are required for full loadplant operation, then the grouping of mills shall be done in such amanner that not more than 3 mills shall be clubbed in one set ofcontroller.e) For each of the functional groups, separate sets of controllers, I/Omodules, communication controllers, power packs/ modules etc.shall be provided. Mixing of hardware of two or more functionalgroups (FG) shall not be acceptable. It shall be ensured that failureof any set(s) of hardware of any FG does not affect other FG(s) anddata communication between other FG(s) and MMIPIS.ii)The control system shall have on-line simulation and testing facility.Further, it shall be possible to on-line configure and tune controllersthrough configuration and tuning station for control system.iii)The system shall have the flexibility to easily reconfigure any controllerat any time without requiring additional hardware or system wiringchanges and without disabling other devices from their normal operationmode. Modifications shall not require switching off power to any part ofthe system.iv) The executive programs for the controller modules shall be firmwarebased, which shall be non-volatile and shall not be alterable except byreplacement of parts. The application programs for the functionalcontrollers shall be software based or firmware based as per OEM'sstandard practice.v) All the 100% hot/redundant backup controllers shall be identical inhardware and software implementation to their corresponding maincontrollers and shall be able to perform all its tasks. The backupcontroller shall track its corresponding main controller. There shall be anautomatic and bumpless switchover from the main controller to itscorresponding backup controller in case of main controller failure and142