Autotuning of Pid Controllers

by Yu, Cheng-Ching

• ISBN13: 9781846280368
• ISBN10: 1846280362
• Edition: 2nd
• Format: Hardcover
• Copyright: 2006-02-10
• Publisher: Springer Verlag

Summary

Recognising the benefits of improved control, the second edition of Autotuning of PID Controllers provides simple yet effective methods for improving PID controller performance. The practical issues of controller tuning are examined using numerous worked examples and case studies in association with specially written autotuning MATLAB(r) programs to bridge the gap between conventional tuning practice and novel autotuning methods.The extensively revised second edition expands and refines on important work in the ubiquitous PID form of control with material covering:• Derivation of analytical expressions for relay feedback responses with tabulated results for easy reference.• The use of shapes of relay responses to generate information for improved closed-loop control and performance assessment.• The applications of autotuning to multiple-model-based cases for handling process nonlinearity.• The use of feedback shapes to generate information for performance assessment.• The impact of imperfect actuators on controller performance.Autotuning of PID Controllers is more than just a monograph, it is an independent learning tool applicable to the work of academic control engineers and of their counterparts in industry looking for more effective process control and automation. Comments on the first edition:This book is written in a way which not only makes it easy to understand but is also useful to those interested in or working with PID controllers.Assembly AutomationThe book will be useful to manufacturers and users of control equipment, and also to researchers in the field of automatic tuning.Automatica

Table of Contents

Introduction	1	(8)
Scope of Process Control	1	(1)
Proportional--Integral--Derivative Control Performance	2	(3)
Relay Feedback Identification	5	(1)
Conclusion	6	(1)
References	7	(2)
Features of Proportional--Integral--Derivative Control	9	(14)
Proportional--Integral--Derivative Controller	9	(4)
Proportional Control	9	(1)
Proportional--Integral Control	10	(2)
Proportional--Integral--Derivative Control	12	(1)
Proportional--Integral--Derivative Implementation	13	(4)
Reset Windup	13	(2)
Arrangement of Derivative Action	15	(2)
Proportional--Integral--Derivative Tuning Rules	17	(3)
Ziegler--Nichols Types of Tuning Rules	17	(2)
Model--based Tuning	19	(1)
Conclusion	20	(1)
References	20	(3)
Relay Feedback	23	(24)
Experimental Design	24	(2)
Approximate Transfer Functions: Frequency-domain Modeling	26	(10)
Simple Approach	27	(3)
Improved Algorithm	30	(2)
Parameter Estimation	32	(1)
Examples	32	(4)
Approximate Transfer Functions: Time-domain Modeling	36	(8)
Derivation for a Second-order Overdamped System	39	(2)
Results	41	(3)
Validation	44	(1)
Conclusion	44	(2)
References	46	(1)
Shape of Relay	47	(28)
Shapes of Relay Response	47	(5)
Shapes	48	(2)
Model Structures	50	(1)
First--order Plus Dead Time	50	(1)
Second--order Plus Small Dead Time	51	(1)
High Order	52	(1)
Identification	52	(10)
Identification of Category 1: First-order Plus Dead Time	52	(1)
Category 1a: True First-order Plus Dead Time	52	(3)
Category 1b: Approximated First-order Plus Dead Time	55	(1)
Identification of Category 2: Second-order Plus Small Dead Time	56	(2)
Identification of Category 3: High order	58	(1)
Validation	59	(3)
Implications for Control	62	(10)
Proportional--Integral--Derivative Control	62	(1)
Category 1: First-order Plus Dead Time	62	(2)
Category 2: Second-order Plus Small Dead Time	64	(1)
Category 3: High Order	64	(1)
Results	64	(6)
Extension	70	(1)
Dead-time-Dominant Process	70	(1)
Higher Order Process	71	(1)
Conclusion	72	(1)
References	73	(2)
Improved Relay Feedback	75	(22)
Analysis	76	(8)
Ideal (On--Off) Relay Feedback	76	(2)
Saturation Relay Feedback	78	(5)
Potential Problem	83	(1)
Improved Experimental Design	84	(5)
Selection of the Slope of Saturation Relay	84	(5)
Procedure	89	(1)
Applications	89	(6)
Conclusion	95	(1)
References	96	(1)
Multivariable Systems	97	(38)
Concept	97	(4)
Single-input--Single-output Autotuning	97	(2)
Multiple-input--Multiple-output Autotuning	99	(2)
Theory	101	(10)
Sequential Design	101	(3)
Process Characteristics	104	(4)
Sequential Identification	108	(3)
Controller Tuning	111	(6)
Potential Problem in Ziegler--Nichols Tuning	111	(1)
Modified Ziegler--Nichols Method	111	(4)
Performance Evaluation: Linear Model	115	(2)
Properties	117	(6)
Convergence	117	(2)
Tuning Sequence	119	(1)
Problem of Variable Pairing	120	(2)
Summary of Procedure	122	(1)
Applications	123	(7)
Moderate-purity Column	123	(1)
High-purity Column	124	(4)
T4 Column	128	(2)
Conclusion	130	(1)
References	130	(5)
Appendix	132	(3)
Load Disturbance	135	(20)
Problems	135	(4)
Step Change versus Continuous Cycling	135	(3)
Effect of Load Change on Relay Feedback Test	138	(1)
Analyses	139	(9)
Causes of Errors	139	(3)
Output-biased Relay Feedback System	142	(2)
Derivation of Bias Value δo	144	(1)
Effect of Load Disturbance	144	(2)
Opposite Effect from Output-biased Relay	146	(2)
Summary of Procedure	148	(1)
Applications	149	(4)
Linear System	150	(2)
Binary Distillation Column	152	(1)
Conclusion	153	(1)
References	154	(1)
Multiple Models for Process Nonlinearity	155	(20)
Autotuning and Local Model	156	(1)
Model Scheduling	157	(6)
Takagi--Sugeno Fuzzy Model	157	(1)
Single Input Systems	158	(2)
Multiple Inputs Systems	160	(2)
Selection of Scheduled Variable	162	(1)
Nonlinear Control Applications	163	(10)
Transfer Function System	163	(4)
Tennessee Eastman Process	167	(6)
Conclusion	173	(1)
References	173	(2)
Control Performance Monitoring	175	(22)
Shape Factor for Monitoring	176	(3)
Shapes of the Relay Feedback	176	(3)
Performance Monitoring and Assessment	179	(9)
Optimal Performance	179	(1)
Proposed Monitoring and Assessment Procedure	180	(1)
Case 1: τI/τ = 1	180	(1)
Case 2: τI/τ > 1	180	(1)
Case 3: τI/τ < 1	181	(3)
Illustrative Examples	184	(4)
Applications	188	(8)
Second-order Plus Dead Time Processes	188	(5)
High-order Processes	193	(3)
Conclusion	196	(1)
References	196	(1)
Imperfect Actuators	197	(22)
Potential Problems	197	(5)
Identification Procedure	202	(4)
Two-step Procedure	202	(3)
Simultaneous Identification	205	(1)
Applications	206	(10)
Linear Systems	206	(1)
Noise-free System	206	(1)
Systems with Measurement Noise	207	(3)
Load Disturbance	210	(2)
Nonlinear Process	212	(1)
Two-step Procedure	212	(1)
Simultaneous Procedure	212	(4)
Conclusion	216	(1)
References	217	(2)
Autotuning for Plantwide Control Systems	219	(26)
Recycle Plant	219	(3)
Control Structure Design	222	(10)
Unbalanced Schemes	222	(1)
Column Overwork	222	(4)
Reactor Overwork	226	(1)
Balanced Scheme	227	(1)
Controllability	228	(3)
Operability	231	(1)
Controller Tuning for Entire Plant	232	(10)
Tuning Steps	233	(1)
Inventory Control	233	(1)
Ratio Control	233	(2)
Quality Loop	235	(3)
Closed-loop Performance	238	(4)
Conclusion	242	(1)
References	242	(3)
Guidelines for Autotune Procedure	245	(14)
Process Characteristics	245	(3)
The Shape	245	(1)
Load Disturbance	246	(1)
Nonlinearity	246	(1)
Noise	247	(1)
Imperfect Actuator	248	(1)
Available Relays	248	(1)
Specifications	249	(7)
Direct Tuning	249	(2)
Model-based Tuning	251	(1)
Multiloop System	252	(4)
Discussion	256	(1)
Conclusion	257	(1)
References	258	(1)
Index	259