Introduction to Aspen DMCplus - Modeling and Building Controllers for Industrial Processes

Course Id:  APC121   |   Duration:  3.00 day(s)   |   CEUs Awarded:  2.1   |   Level:  Introductory


Course Objective

In this course you will learn the characteristics of linear, dynamic, and empirical models and use Aspen APC Builder to configure and tune DMCplus controllers. You will learn about Aspen DMCplus calculation modules and the sequence of calculations, DCS connections and other specific features of of DMCplus controllers including ramp handling, subcontrollers, and external targets.

This course is equivalent to the final three days of APC101: Introduction to Aspen DMCplus for APC Engineers.

Course Overview

  •  Learn how to conceive, design and deploy an Aspen Advanced Process Control (APC) Application
  •  Learn the characteristics of a Linear, Dynamic, Empirical Model
  •  Learn how to use DMCplus Model to identify a Process Model
  •  Be able to decide when to use FIR or SubSpace Modeling
  •  Understand the importance of Collinearity Analysis
  •  Learn to use the DMCplus Build and DMCplus Simulate software to develop control models, build control applications, and perform off-line tuning and simulation of control applications   
  •  Learn the role of CV Ranks and Equal Concerns in the computation of the Steady State Targets
  •  Learn to use MV/CV Costs to cause the steady state optimization to seek the most profitable operating point
  •  See why multiple moves are calculated for each control cycle
  •  Learn how to use MV move suppression and CV Concerns to tradeoff move minimization versus CV error minimization
  •  Learn how to implement variable transformations and custom built controller calculations

Benefits

  •  Acquire the skills and knowledge required to participate on or lead a team charged with the development and deployment of an Advanced Process Control application
  •  Know how to use DMCplus Model to identify a controller model before implementing the controller online
  •  Increased effectiveness in troubleshooting and maintenance of Aspen DMCplus controllers
  •  Increased awareness of the operating characteristics and capabilities of Aspen DMCplus controllers

Audience

  •  Engineers who are maintaining existing Aspen DMCplus controllers
  •  Engineers who are designing or implementing new Aspen DMCplus controllers
  •  Operating supervisors and console operators who are involved in Aspen DMCplus control projects

Approach

  •  Introduction to basic concepts behind  multivariable control
  •  Description of the theoretical concepts that form the basis of the Aspen DMCplus family of products
  •  Demonstrations of the ways in which the offline tools are used
  •  Hands-on workshops that allow controller development concepts to be applied to typical plant processes
  •  Concept review quizzes reinforce learning

Prerequisites

  •  Background in chemical process engineering and/or process operations
  •  APC120 Introduction to aspenONE Advanced Process Control - Operating and Maintaining Controllers Online

Subsequent Courses

This course serves as a prerequisite for many of the more advanced courses.

  •  APC210 Aspen Watch Performance Monitor: Real Time Monitoring and Maintaining Controllers Online
  •  APC230 Aspen DMCplus: APC Project Pretesting Using a Virtual Plant
  •  APC240 Aspen DMCplus: APC Project Step Testing and Commissioning Using a Virtual Plant
  •  APC250 Aspen DMC3: APC Calibrate and Aspen Adaptive Modeling

Class Schedule

Class Agenda

APC121: Introduction to Aspen DMCplus - Modeling and Building Controllers for Industrial Processes

Modeling Terminology

  •   Differentiate between Real Time Optimization and Advanced Control
  •   Discuss the characteristics of an independent variable and a dependent variable
  •   Review the definitions of a Unit Response Curve, Time to Steady State, and Steady State Gain
  •   Review the defining characteristics of an Aspen DMCplus Controller and the components comprising an Aspen APC Suite
  •   Introduction to Aspen DMC3

APC Project Overview
  •  Review the process for implementing an APC project
  •  Discuss available alternatives and proper documentation procedures

Dynamic Modeling of Linear Systems
  •   Review the definition of a dynamic, empirical, linear model and the technology of Finite Impulse Response (FIR) Modeling
  •   Discuss the strengths and drawbacks of an FIR model

Model Identification using DMCplus Model
  •   Familiarization with the DMCplus Model interface
  •   Use the vector import tool to bring data into DMCplus Model
  •   Review vector quality and perform data processing
  •   Define and run model identification cases
  •   Workshop: Fractionator Controller - Build a finite impulse response model for a simple fractionator

Model Analysis in DMCplus Model
  •   Define and Run Predictions
  •   Understand and use model analysis tools
  •   Workshop: Fractionator Controller - Evaluate and assemble the model
  •   Workshop: Fractionator Controller - Fix collinearity issues in the model

Variable Transformations
  •   Configure built in transforms to deal with non-linear data
  •   Configure transforms to rescale data
  •   Workshop: Fractionator Controller - Apply variable transformation

SubSpace Identification Technology
  •   Review modeling technology for MPC control
  •   Subspace Identification: fundamentals and features
  •   Aspen DMCplus - guidelines for Subspace modeling
  •   Workshop: Fractionator Controller - Build a subspace model for the fractionator 

Open Loop Prediction
  •   Learn how DMCplus uses the dynamic model to predict the future behavior of controlled variables
  •   Learn how DMCplus accounts for differences between the prediction and the actual measurements
  •   Learn how DMCplus corrects predictions for ramp variables
  •   Learn how prediction errors can be used to assess modeling errors
  •   Workshop: Fractionator Controller - Configure prediction error filter options

Steady-State Feasibility Check
  •   Introduce the DMCplus Steady State Optimization features
  •   Recognize how DMCplus uses the Steady State Predictions in Projecting the Optimum Operating Point for the Process
  •   Differentiate between a Linear Program and a Quadratic Program

Economic Optimization
  •  Determine how MV Costs can be used to drive the Process to an Economic Optimum
  •  Determine how an external Optimizer can affect the DMCplus Steady State Solution
  •  Workshop: Fractionator Controller - Calculating Steady State Cost and configuring the Steady State Optimizer

Minimizing Dynamic Errors
  •  Introduce DMCplus Dynamic Move Calculations features
  •  Discuss how computing multiple future moves improves control
  •  Understand tradeoffs between move aggressiveness and error minimization
  •  Explain how ramps are controlled dynamically
  •  Review details of the Move Calculation

Using DMCplus Build and DMCplus Simulate
  •  Build Controller Configuration Files (CCF) using DMCplus Build
  •  Write custom calculations using DMCplus Build
  •  Review tuning and simulate controller operation using DMCplus Simulate
  •  Workshop: Fractionator Controller - Configure the CCF file using DMCplus Build
  •  Workshop: Fractionator Controller - Dynamic Tuning to adjust move suppressions to achieve smooth control

Calculations and Gain Scheduling
  •  Configure input and output calculations to modify controller data
  •  Configure gain scheduling to modify model gains on the fly
  •  Configure and manage model switching
  •  Workshop: Fractionator Controller - Configure custom built controller calculations

External Targets
  •  Identify and explain the application of External Targets:
  •  External Target Definitions
  •  RTO and IRV Style External Targets
  •  External Target Attributes

Subcontrollers
  •  Identify and explain subcontroller concepts
  •  Discuss MV and CV memberships in Subcontrollers
  •  Subcontrollers and shedding
  •  Introduction to Composites

Ramp Variable Techniques
  •  Learn how to deal with process ramp variables by using one of the following types:
  •  Balanced Ramps
  •  Ramps with allowed Imbalance
  •  Program Imbalance Ramps
  •  Pseudo-ramps
  •  Discuss the effects of the ramp horizon on ramp calculation
  •  Workshop: DemoCol Controller - Observe the effects of changing tuning parameters on ramp behavior

New Features in Aspen APC Suite
  •  Review the new features available with Aspen DMC3 controllers

Appendix: Controller Variable Validation
  •  Learn how to deal with the Controller's variable validation process:
  •  General Variables
  •  Manipulated and Feedforward Variables
  •  Subcontrollers and Composite
  •  External Targets

Aspen Technology, Inc. awards Continuing Education Units (CEUs) for training classes conducted by our organization. One CEU is granted for every 10 hours of class participation.