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Specific steps:
Step 1: Prophase design of the controller. Before using the predictive con-
troller, designers should be familiar with relevant knowledge of the process and
have more discussions with operators and technicians to complete the prophase
design of the controller. During the implementation of the program, designers
may need to communicate and discuss with technicians to determine the manip-
ulated variables, disturbance variables and controlled variables of the predictive
controller.
Step 2: Preliminary checkout of the process data, In the preliminary checkout
of the process data, designers need to make sure whether the variable signals
of the predictive controller are normal. The breakdown of any transmitters and
valve related to variables need to be repaired to ensure the safe and effective
operation of the controller.
Step 3: Test of the process data.If variables which are relevant to the controller
are normal, further test should be conducted on the controlled object. Test is
the process of performing disturbance experiment on every input variable and
at the same time recording and collecting data. The test of process object is
very crucial. Accurate test will shorten the time of the test run and ensure the
long-term and stable operation of the controller.
Step 4: Identification of the process model.After the data test, the data ob-
tained from the object test can be used to obtain the transfer function matrix
through system identification.
Step 5: Building controller configuration files and simulation and adjust-
ment for controller off-line.With the identified model, upper and lower limits
of the disturbance variables, controlled variables, and manipulated variables are
determined using the simulation model in simulation. After evaluation of the
controller's performance, parameters can be further adjusted in order to reach
expected performance.
Step 6: Online test of controller. The online test of the predictive controller
runs firstly in test mode to test whether the software is operating normally as
well as examine the accuracy of the model. Under this mode, the controller will
accomplish all algorithms whose output however will not be added to the con-
trolled object. All upper and lower limits of control variables will be fixed within
the range very close to the current set value. Then predictive controller is started
meanwhile the performance of the controller is monitored and adjustments will
be made if necessary.
Step 7: Maintenance of the predictive controller.Maintenance is needed to en-
sure the optimal performance for any kind of predictive controller. An important
measure often taken is to detect the upper and lower limits of manipulated and
controlled variables. Another important measure is update costs for steady state
variable.
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