Design of Safety Control for Gas turbine using PLC
Gas Turbines are one of the most efficient equipment for converting fuel energy to mechanical energy. A gas turbine is a machine delivering mechanical power or thrust to the generator with maximum efficiency. Gas turbine functions in the same way as the Internal Combustion engine. It sucks in air from the atmosphere, compresses it. The fuel is injected and ignited. The gases expand doing work and finally exhausts outside. The three main sections of a Gas Turbine are the Compressor, Combustor and Turbine. The gas turbine power plant has to work continuously for long period of time without output and performance decline. Apart from the main sections there are other important Auxiliaries systems which are required for operating a Gas Turbine Power Plant on a long term basis.
In our project, the gas turbine and generator controls will be implemented using Programmable Controller Logic. The project discusses control issues for each equipment such as air filter, compressor, combustion chamber, turbine and generator. Increasingly with gas turbine engine control, there is competitive pressure to provide more and more sophisticated controls, while at the same time reducing cost. Hence optimal logics to be developed.
Design of Sequential Logic system for Instrumentation Air Plant using PLC
Air compressors have many uses, including: supplying high-pressure clean air to fill gas cylinders, supplying moderate-pressure clean air to a submerged surface supplied diver, supplying moderate-pressure clean air for driving some office building pneumatic HVAC control system valves, supplying a large amount of moderate-pressure air to power pneumatic tools, such as jackhammers, filling high pressure air tanks (HPA), for filling tires, and to produce large volumes of moderate-pressure air for large-scale industrial processes (such as oxidation for petroleum coking or cement plant bag house purge systems).
The aim of our project is to understand the existing logic by reading the plant manufacturers manuals, finding out the scope for writing logical statements, converting the logical statements into flow charts, developing ladder diagram for the flow chart, test the logic in simulation mode and commission the control system.
Design of Emergency Shutdown system for Steam Turbo Generator using PLC and SCADA
The purpose of a generator is to generate electrical power at higher voltages which can be used for industrial applications. There are plenty of factors related to the generator control process. Since it involves large values of voltage and current controls, they must be maintained within the prescribed limits to enable safe and profitable running of the process. Even a slight miscalculation or misjudging of certain parameters may cause monumental damage to the machinery and also to valuable human lives involved. In the recent ages all the controlling processes are carried out by programmable logic controller which is programmed to the customer’s requirements.
The predominant parameters or interlocks involved are
- Lube oil pressure
- cooling system temperature
- compressor cooling method
- Condensate extract pump system
- Turbine control
- Generator controls
Safety Integrity Level (SIL) based logical control for Liquified Natural Gas (LNG) Compressor using PLC
The Natural Gas enters into a knockout drum for removal of any moisture / liquid particles. Any liquid in the gas will settle at the bottom of the knockout drum and displaced by a liquid pump. The gas enters into the Compressor, where the pressure is increased from 0.13 Kg/Cm2 to 2.5 Kg/cm2. The Compressor is supplied with cooling water and lube oil for its proper functioning.
A Programmable controller will be deployed to control the Gas Compressor. PLC hardware and software will be designed and implemented in site. Safety Integrity Level is a way to indicate the tolerable failure rate of a particular safety function. There are four discrete integrity levels associated with SIL. The higher the SIL level, the lower the probability of failure on demand for the safety system and the better the system performance.
Design of Feed Forward System for Surge Drum Level in industries using PLC
A suitable independent control system to be developed which can measure the disturbance and automatically correct the level accordingly. We suggest that the Feedforward control will suppress the disturbance before it has had the chance to affect the level. This requires the capacity to anticipate the effect of perturbations on the system’s goal. Otherwise the system would not know which external fluctuations to consider as perturbations, or how to effectively compensate their influence before it affects the system. This requires that the control system be able to gather early information about these fluctuations. In addition to this the process variables to be stored for future use. PLC will be used to monitor and control the process effectively.