To provide students with a detailed knowledge and understanding of the principlesbehind final control elements, process control methods, process dynamics and controller tuning techniques. It will also equip students with the skills to configure, optimise and diagnose closed loopcontrol systems.
Final Control Elements
Control valve types including: ball valves, globe valves, pinch valves. Control valve actuators including: pneumatic, hydraulic and electricalactuators. Valve positioners: operation, fitting and optimization of valve positioners and I/P convertors. Control valve application, selection,sizing, noise reduction. Control valve characteristics and rangeability. Other final control element types including: variable speed drivenpumps, thyristor controlled heating elements.
Control Strategies
Open-loop control, closed-loop control, instrument response time, process lags including distance/velocity and transfer lags. On-off control,P control, PI control, PID control. Advanced control techniques including: cascade, ratio and feed-forward control. Case studies usingdifferent control modes.
Process Dynamics
Process characteristics:self regulating and integrating processes, process gain, process time constant, dead time, first order systems, higher order systems. Dynamic response testing: open loop response testing, closed loop (continuous cycling) testing, ultimate gain, ultimate period.
Controller Tuning
Trial and error tuning methods, reaction curve (open loop) method of controller optimisation, continuous cycling (closed loop) method ofcontroller optimisation. Tuning algorithms: Ziegler Nichols, Cohen and Coon, Lambda, dead time rule. Practical tuning exercises: implementation and tuning of control loops utilising stand-alone and PLC based PID controllers.
PLCs in Control Applications
PLC hardware: digital I/O, analogue I/O, communication modules. Review of programming functions. IEC 1131-3 programming languages standard: function block programming. Analogue signal interfacing: 0-10 V, 4-20mA signals. Advanced PLC programming functions including: data movement and comparison functions, scaling functions, arithmetic functions, subroutines, PID control. Fault finding in PLC programs.
Monitoring of Analogue Variables
Data acquisition and monitoring devices: HMIs, SCADA systems, digital and paper based chart recorders, DAQ devices.
PLC based Control Projects
PLC project planning: instrumentation selection and implementation, final control element selection and implementation, programming requirements, wiring drawings, initial program development. PLC project implementation: hardware installation and wiring, program implementation. PLC project testing and commissioning: I/O device loop checking and/or simulation, loop tuning and optimisation, systematic fault finding of system faults. Project documentation: P & ID drawings, description of control objectives, I/O schedules and wiring diagrams, fully commented program, software back-ups.
| Module Content & Assessment | |
|---|---|
| Assessment Breakdown | % |
| Other Assessment(s) | 50 |
| Formal Examination | 50 |