PID Controller Course

Lesson 1 • Open-Loop vs. Closed-Loop Control

Contrasts feedforward and feedback architectures using block diagrams. Students gain intuition for why feedback is essential to reject disturbances.

Lesson 2 • Why Automatic Control Matters

Examines real-world consequences of uncontrolled processes and the economic case for automation. Anchors the entire course in practical motivation.

Lesson 3 • Sensors, Actuators, and Transmitters

Covers the physical hardware that connects a controller to a process. Students learn signal ranges, scaling, and common failure modes.

Lesson 4 • Control Loop Terminology

Standardises terms such as setpoint, error, process variable, and span used in every subsequent chapter. Prevents misinterpretation of controller parameters.

Lesson 1 • Higher-Order and Integrating Processes

Extends modelling to second-order and pure-integrating processes common in level and batch control. Prepares students for tuning challenges in later chapters.

Lesson 2 • First-Order Process Models

Derives and applies the first-order plus dead-time (FOPDT) model used in most PID tuning methods. Students fit FOPDT parameters from step-test curves.

Lesson 3 • Transfer Functions and Block Diagrams

Introduces Laplace-domain transfer functions as a compact process description. Students manipulate block diagrams to find closed-loop transfer functions.

Lesson 4 • Understanding Process Response

Introduces the concept of dynamic response and why it determines controller design choices. Connects process physics to mathematical descriptions.

Lesson 1 • Controller Output and Modes

Examines manual, automatic, and cascade output modes and bumpless transfer between them. Students configure mode switching without process upsets.

Lesson 2 • Combined PID Equation Forms

Presents parallel, series, and ideal PID forms and explains how parameter values differ across forms. Students convert parameters between forms accurately.

Lesson 3 • Integral Action and Reset

Covers how integral action accumulates error over time to eliminate offset. Students learn reset rate, integral windup, and anti-windup strategies.

Lesson 4 • Proportional Action Fundamentals

Explains how proportional gain scales the error to produce a corrective output. Students observe offset behaviour and understand why P-only control has steady-state error.

Lesson 1 • IMC-Based Tuning

Derives PID parameters from internal model control theory using a single closed-loop time constant. Students tune for robustness by adjusting the lambda parameter.

Lesson 2 • Lambda Tuning for Integrating Processes

Adapts lambda tuning specifically for level and flow integrating loops. Students avoid the instability that standard rules cause on non-self-regulating processes.

Lesson 3 • Ziegler-Nichols Tuning Rules

Applies the classic open-loop and closed-loop Ziegler-Nichols methods to FOPDT models. Students calculate Kp, Ti, and Td and understand the method's aggressive bias.

Lesson 4 • Tuning Objectives and Trade-offs

Defines performance criteria—setpoint tracking, disturbance rejection, and robustness—and shows they conflict. Students select objectives before choosing a tuning method.

Lesson 1 • Robustness to Process Changes

Analyzes how process gain and time-constant variations degrade a fixed-tuning controller. Students apply detuning strategies to maintain stability across operating ranges.

Lesson 2 • Performance Metrics and Benchmarking

Quantifies loop performance using rise time, overshoot, settling time, and integrated error indices. Students benchmark a tuned loop against a defined performance target.

Lesson 3 • Diagnosing Loop Performance Problems

Teaches pattern recognition on trend charts to identify oscillation, offset, sluggishness, and noise. Students link each symptom to a specific parameter adjustment.

Lesson 4 • Frequency-Domain Stability Margins

Introduces gain margin and phase margin as robustness measures derived from Bode plots. Students calculate margins and relate them to safe operating gain ranges.

Lesson 1 • Feedforward Control Integration

Adds a feedforward path that compensates for measured disturbances before they affect the controlled variable. Students design static and dynamic feedforward compensators.

Lesson 2 • Ratio Control Systems

Configures ratio control to maintain a fixed proportion between two process streams. Students apply ratio stations and handle wild-stream variations.

Lesson 3 • Cascade Control Design

Explains how an outer primary loop drives the setpoint of an inner secondary loop to reject inner disturbances faster. Students size and tune both loops in sequence.

Lesson 4 • Smith Predictor for Dead-Time Compensation

Applies the Smith predictor structure to improve control of processes with large dead time relative to time constant. Students implement and tune the predictor model.

Lesson 1 • Discrete-Time PID Algorithms

Converts continuous PID equations to position and velocity algorithms suitable for digital execution. Students select scan time relative to process dynamics.

Lesson 2 • Signal Conditioning and Filtering

Applies input filters to reduce measurement noise before it enters the PID calculation. Students design first-order filters and evaluate the filter time-constant trade-off.

Lesson 3 • Commissioning and Loop Checkout

Provides a structured commissioning sequence from hardware verification to closed-loop handover. Students execute loop checkout procedures and document results.

Lesson 4 • Alarm and Interlock Integration

Integrates process alarms and safety interlocks with PID controller logic. Students configure alarm limits, deadbands, and interlock-driven mode changes.

Lesson 1 • Control Performance Monitoring

Implements statistical and index-based methods to continuously monitor loop performance without manual inspection. Students calculate Harris index and variance-based metrics.

Lesson 2 • Re-Tuning and Parameter Updating

Defines when and how to re-tune a loop after process changes, equipment replacement, or performance degradation. Students follow a safe re-tuning protocol on live loops.

Lesson 3 • Valve and Actuator Diagnostics

Identifies control valve problems—stiction, hysteresis, and positioner faults—that cause limit cycling. Students apply bump tests and signature analysis to quantify valve health.

Lesson 4 • Continuous Improvement Culture

Embeds loop performance improvement into routine plant operations using KPIs, audits, and cross-functional reviews. Students design a loop health audit programme.