Protection and interlocks of critical equipment in power stations using PLC

Our aim of the project is to demonstrate all the protections and interlocks available in the critical equipments of power station such as Boiler, Turbine, the Alternator, and how these critical equipments are protected from abnormal conditions and parameters. The failure of any one of these equipments will lead to loss of power generation. The cost of these equipments is huge. Boiler has got protection against abnormal drum level, abnormal live steam pressure, abnormal live steam temperature, abnormal furnace pressure. Turbine has got protection against abnormal condenser vacuum, abnormal lubricating oil pressure, abnormal axial shiftand abnormal turbine speed. Similarly the generator has also got the following protections 1.10.5kv earth fault, 220kv earth fault, differential protection, incomplete phase condition, rotor earth fault, stator inter turn fault, over current protection, stator overvoltage, rotor overvoltage. These protections are classified as class a, class b and class c protections. Distributed digital controls and numerical protections relays play vital role in providing protections to critical equipments to demonstrate these protections in real sense in our project kit. However an effort has been made to demonstrate the functioning of these protections with the aid of a programmable logic controller. Also a few suggestions to improve the existing system are also discussed.