Model Predictive Control Professional Plus function block parameters

None

The indication that a block error condition associated with the MPCPlus block not selected in BAD_MASK is True (Active).

None

The indication that a block error condition associated with the MPCPlus block selected in BAD_MASK is True (Active).

None

The set of active error conditions that triggers a user-defined Bad condition. The user selects a subset of block error (BLOCK_ERR) conditions in the BAD_MASK parameter. When any of these conditions is True, the BAD_ACTIVE parameter becomes True. When any of the BLOCK_ERR conditions not included in BAD_MASK is True, ABNORM_ACTIVE becomes True.

EU of associated manipulated parameter.

The backcalculation value and status (BKCAL_OUT, RCAS_OUT, or ROUT_OUT) from a process input block that is Manipulated by the MPCPro block. This value and status are used by the MPCPlus block for bumpless transfer and to determine active limit conditions and whether the downstream block is in the correct mode. The number shown as part of the BKCAL_IN parameter name corresponds to the number contained in the Name field for the associated Manipulated parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

None

The actual error status of the function block.

None

CV blocking causes the successive equations of the dynamic matrix to be added together to speed up calculations. This is essentially equivalent to defining future intervals of unequal duration. CV blocking can be described by the vector where the vector components represent the number of successive equations to accumulate.

The sum of CV blocking vector components ∑ satisfy the equation:

∑ = PH +CH-1

Where:

PH - prediction horizon =120

CH - control horizon up to 40

If the user defined CV blocking vector does not satisfy the above equation, the CV blocking last component will be adjusted as required automatically.

Default CV Blocking assumes the default MV control horizon =14.

Default CV blocking is: [ 1; 1; 1; 1; 1; 1; 1; 1; 2; 3; 3; 4; 5; 7; 9; 12; 20; 20; 20; 20]

None

The DeltaV system preserves the prediction horizon for CVs and AVs during a partial download of the MPCPlus block. When FOLLOW is True (1), the system sets the entire prediction horizon for each CV and AV to its current value.

None

Indicates if Inspect is enabled and one or more of the limits for the block have been exceeded. The normal value is 0. This parameter is set to 1 if both of the following conditions are True:

• The Write To Inspect Alarm context menu item was selected from Inspect for this block.
• With the Current Hour filter selected, Inspect indicates that an abnormal condition exists for Mode, Control, Input, or Variability.

None

Shows and sets the block operating state. MODE contains the actual, target, permitted, and normal modes.

None

MV blocking vector provides a subset of the future moves within the control horizon that are calculated. The default control horizon = 14 and the default MV blocking vector is [1,2,3,4,5,7,9,14]. The maximum control horizon = 40 and the maximum number of calculated control moves = 16.

The first zero component in the vector terminates the control horizon.

None

Indicates if the MV is at its high or low limit. This parameter is defined as unsigned integer array where the array element number corresponds to the number appearing in the Manipulated parameter name; for example limit indication for PROC_IN3 is in element number 3.The following meaning is assigned to the element values:

• 0= Not limited
• 1= Low limited
• 2=High limited
• 3=Constant

% of limit range

The amount that the MV must move away from the MV limit (after hitting the limit) before it is not considered to be operating at the limit. This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Manipulated parameter name; for example limit indication for PROC_IN3 is in element number 3. A value of 100 disables limit flagging and display

% of time

The percent of time the MV was operating at its limit since the calculation was last reset (by POT_RESET). This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Manipulated parameter name; for example limit indication for PROC_IN3 is in element number 3.

$ per unit time

The profit associated with the current operation based on the current objective and its associated costs.

$ per unit time

The optimized profit that can be achieved based on the current control objective and its associated costs.

None

Indicates if the Control or Constraint parameter is outside its range or over its high or low limit. This parameter is defined as an integer array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5. The following meaning is assigned to the element values:

• 0= Not Exceeded
• 1= Exceeded

% of EU span

The amount that the control or constraint parameter must return within its constraint or range limit (after exceeding the limit) before it is considered to be operating within its limit. This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5. A value of 100 disables limit flagging and display.

% of time

The percent time the Control or Constraint parameter was operating above its constraint or range limit since the calculation was last reset (by POT_RESET). This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5.

None

Indicates if the Control or Constraint parameter is operating at its range or its high or low limit. This parameter is defined as an integer array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5. The following meaning is assigned to the element values:

• 0= Not limited
• 1= Low limited
• 2=High limited
• 3=Constant

% of EU span

The amount that the control or constraint parameter must return within its constraint or range limit (after exceeding the limit) before it is considered to be operating within its limit. This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5. A value of 100 disables limit flagging and display.

% of time

The percent time the Control or Constraint parameter was operating at its constraint or range limit or constant status since the calculation was last reset (by POT_RESET). This parameter is defined as a floating array where the array element number corresponds to the number appearing in the Control or Constraint parameter name; for example limit indication for PROC_OUT5 is in element number 5.

None

Parameter used to reset the MPCPlus calculation of the percent time Control, Constraints, and Manipulated parameters were at their limit. Also, this parameter resets the calculation of the percent time Control or Constraint parameters were above their limit.

Seconds

The percent of time MPCPlus is limited over the period of time that has elapsed since the MPCPlus block's performance monitoring calculations or above limit were reset.

The output units of the connected block MPCPlus outs - Process Ins.

Shows the value and status of Disturbance and Manipulated parameters, such as the inputs to the process, read by the MPCPlus block .

The number shown as part of the PROC_IN parameter name corresponds to the number contained in the Name field for the associated Disturbance and Manipulate parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

Note: Since the Move option is provided to change a Disturbance parameter to a Manipulate parameter, a Name is assigned automatically to all N process inputs (Disturbance and Manipulate). This number, associated with a process input, remains the same even when the Move option is used to change its use in the MPCPro block.

The output units of the connected block

Proc outs - MPCPlus ins.

Shows the value and status of Control and Constraint parameters, such as the outputs of the process read by the MPCPlus block.

The number shown as part of the PROC_OUT parameter name corresponds to the number contained in the Name field for the associated Control or Constraint parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

Note: Since the Move option is provided to change a Control parameter to a Constraint parameter, a Name is assigned automatically to all M process outputs (Control and Constraint parameters). This number, associated with a process output, remains the same even when the Move option is used to change its use in the MPCPlus block.

Units of connected input

Parameter that provides a measurement value or calculated value for process throughput. This value and its associated status can be written directly to the PROD_RATE parameter or provided through a connection to the parameter (if Show Parameter is selected).

None

Enables automatic correction for changes in the response delay that are associated with process throughput as indicated by PROD_RATE.

None

Maximum value of PROD_RATE_FACTOR that is used in compensating for changes in transport delay.

None

The calculated ratio of the normal production rate to the current production rate as indicated by PROD_RATE_NORMAL and PROD_RATE respectively. Limited to 1- maximum value specified by PROD_RATE_F_LIM.

Units of Prod_Rate

The value for throughput when the MPCPlus block was commissioned. It is recommended that MPCPlus be commissioned at maximum throughput if the automatic corrector for changes in response delay is used.

The units of the associated control parameters.

Shows the value and status of the remote setpoints provided by another function block or application. These will be used as the MPCPlus block setpoint when the actual mode of the MPCPlus block is RCAS.

The number shown as part of the RCAS_IN parameter name corresponds to the number contained in the Name field for the associated Control parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

Note: Since the Move option is provided to change a Control parameter to a Constraint parameter, a number is assigned automatically to all N process outputs (Control and Constraint parameters). This number, associated with a process output, remains the same even when the Move option is used to change its use in the MPCPlus block.

The units of the associated control parameters.

Shows the backcalculation value and status provided to another function block or application that is writing a remote setpoint to the RCAS_IN parameter. The number shown as part of the RCAS_OUT parameter name corresponds to the number contained in the Name field for the associated Control parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

Note: Since the Move option is provided to change a Control parameter to a Constraint parameter, a Name is assigned automatically to all M process outputs (Control and Constraint parameters). This number, associated with a process output, remains the same even when the Move option is used to change its use in the MPCPlus block.

None

Normally, an error occurs between the process measurement and the process model prediction due to a mismatch between the process and process model and to unmeasured disturbances not included in the model. The error is compensated every scan by matching the prediction for a current scan with the current measurement and shifting the output prediction up or down. This works well for self-regulating types of processes. For integrating outputs, the following specific effects must be accounted for:

• A fraction of the error attributed to the model mismatch and to the integrating types of unmeasured disturbances can integrate in the future.
• Some fraction of the error will not integrate in the future and the error should be corrected by normal shift.

This can be written as the following equation:

• ERROR = SHIFT + ROTATION = ERROR (Shift Factor + Rotation Factor)
• Shift Factor + Rotation Factor = 1.0
• Rotation Factor = 1.0 - Shift Factor

The Rotation Factor is the Integrating Gain in the period of one MPC scan for unmeasured disturbances and process model mismatch; usually in the range 0.0 to 0.1.

None

Defines the action to be taken on remote control device timeout.

Seconds

The maximum allowable time between RCAS_IN or ROUT_IN updated. Mode shedding occurs if this time is exceeded.

None

Consecutive time (expressed in multiples of Time to Steady State ) that the simulated value of a Control or Constraint parameter that has been configured for Simulate failure action is used in control before the MPCPlus block takes the configured shed mode action.

The units of the associated process output parameters.

Shows the setpoints used by the MPCPlus block. This value can be set by an operator (in Auto mode) or indirectly by a function block or application when the mode is RCAS (and remote setpoint capability has been selected for the Control parameter). The number shown as part of the SP parameter name corresponds to the number contained in the Name field for the associated Control parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

The units of the associated process output parameters.

Shows the working setpoints used by the MPCPlus block. This value can differ from the operator setpoint on a setpoint change based on the setpoint filter. Also, the optimizer can change the working setpoint within the setpoint range to meet a selected objective. If infeasibility occurs, the optimizer may move the working setpoints of the lowest priority variables outside the configured setpoint range to protect higher priority variables. In this case, a yellow border appears on the associated faceplate and the output is flagged as Limit Exceeded on the Optimizer dialog in the MPC Operate Pro application. The number shown as part of the SP_WRK parameter name corresponds to the number contained in the Name field for the associated Control parameter in the MPCPlus Properties dialog when the Advanced tab is selected.

None

Status options allow you to select options for status handling and processing. The only supported status option is Use Uncertain as Good

Percent of scale

The largest standard deviation calculation for the control parameters over the Time to Steady State.

Percent of scale

The estimated capability standard deviation (measurement of short term variation) over the Time to Steady State. An estimate of the least standard deviation the process could achieve ideally.

Percent

Used to calculate a process parameter's standard deviation percent of time out of standard deviation limit

Percent

The process output variability

Percent

Used to calculate of the percent of time the variability limit is exceeded