Day 1
Introduction
to regulatory control.
The
actual state of regulatory controls in the real world.
Why
controls are operating so badly.
Description
of the feedback control loop, terminology, definitions, and nomenclature.
The
importance of measurement in control.
Understanding
the supplier’s terminology and specifications.
Accuracy,
stability, and repeatability.
Pressure
measurement:
Gauge and absolute pressure.
Pressure gauges.
Manometers.
The differential and absolute pressure transmitter.
Flow
measurements:
Positive displacement meters.
Differential pressure measurement, the orifice plate, pitot tube, and
averaging pitots.
Magnetic flow meter.
Target meters.
Vortex meter.
Doppler flowmeters.
Ultrasonic flowmeters.
Coriolis mass flow meter.
Level
measurements:
Float and cable.
Discrete level measurements using multiple switches.
Hydrostatic head level measurement.
Dip tubes.
Level probes including conductive, capacitive, inductive.
Ultrasonic level measurement.
Microwave and laser level
measurements.
Nuclear level measurement.
Temperature
measurements;
The thermometer.
Filled systems.
Thermocouples, and associated components and problems.
Resistance thermometers and measuring techniques.
Thermistors and other semiconductor sensors.
Optical pyrometers and radiation measurements.
Density
measurement:
Hydrostatic method.
Nuclear method.
The
transmitter.
Analogue and digital signal transmission.
Smart transmitters.
Dynamic accuracy and scan rate.
Digital signal aliasing.
Analogue signal aliasing.
Noise and
disturbances in real life processes.
How to look at
measurements.
Filtering, dangers
and rules.
The
Process
The 2 classes of processes (self regulating and integrating).
Elementary
Process Dynamics
Process gain.
Dead time.
The first order lag.
Brief description of other, more advanced dynamics.
Day 2
Final
control elements:
Purpose.
Types.
The need for good valves.
Linearity.
Inherent and installed characteristics.
Linearising incorrect installed characteristics.
Positioner recommendations.
Hysteresis and deadband.
Negative hysteresis.
The slip-stick cycle, and a solution.
Recommended on-line valve test system.
Workshop on valve problem analysis.
PID
Controller Workshop
The importance of understanding your controllers.
Possible complex features of a modern digital controller.
Controller algorithms and implementations.
Controller test set-up.
The P only controller.
The I term.
Reset windup, and anti-reset windup (internal and external).
The D term.
The derivative filter.
The full PID controller.
PID, PI-D, and I-PD controller actions and their importance.
Controller
scan rate.
Control
Loop
Analysis – Test
Procedures
Understanding the operation of the system.
Determining the testing sequence.
The three types of tests for both self regulating and integrating
processes.
Day 3
Tuning
Methods available.
“Swag” tuning.
Step response tuning rules.
Self-regulating processes tuning workshop.
Integrating processes tuning workshop.
Tuning non-linear systems correctly.
Ratio
Control
Cascade
Control
The need for cascade control.
Optimizing cascade systems.
Surge
and Averaging Level Control Techniques.
A different approach, as opposed to fast, or “tight” level control.
Practical
Examples
A look at many problem loops taken from plants around the world.
Day
4
The
Process Transfer Function
Establishing the process transfer
function.
The need for the process transfer
function.
Feedforward
Control
The effect of load changes on a heat
exchanger with no control.
Heat exchanger with feedback control.
Dynamic feedforward control on the
heat exchanger.
Cancelling load change effects.
Calculating feedforward tuning
parameters.
Connecting the analyser for feedback
and feedforward tuning.
Advantages of feedforward.
Feedforward tuning workshop.
Control
of Processes with Complex Dynamics.
Long deadtimes.
Multiple lags.
Second order lags
Negative and positive leads
on self regulating and integrating processes.
