| Series Editors' Foreword | p. vii |
| Preface | p. ix |
| Introduction | p. xi |
| Notation | p. xxiii |
| Introduction to Gas Turbine Engine Control | p. 1 |
| Introduction | p. 1 |
| Calculation of Effective Thrust | p. 2 |
| Military Engine Example | p. 3 |
| Engine Control Programs | p. 5 |
| On-Line Optimization | p. 8 |
| Example of Maximum Distance Calculation at Cruise Flight | p. 9 |
| Power Plant Efficiency | p. 10 |
| Limitations of Current Controllers | p. 11 |
| Design of Optimizing Control | p. 12 |
| Concluding Remarks | p. 13 |
| Gas Turbine Models | |
| Models and the Control System Design Cycle | p. 17 |
| Introduction | p. 17 |
| Mathematical Models and Controller Life Cycle | p. 17 |
| Design Stage Models | p. 19 |
| Experimental Demonstration and Production Stage Models | p. 19 |
| In-Service Use Models | p. 19 |
| Dynamic Modelling Techniques | p. 20 |
| Dynamic Modelling for Control Systems Development | p. 21 |
| Dynamic Characteristic | p. 22 |
| Adaptation of Controller Structure and Parameters at the Design Stage | p. 23 |
| Linear Dynamic Models | p. 24 |
| Real-time Piecewise Linear Dynamic Models | p. 24 |
| Control System Testing | p. 25 |
| Concluding Remarks | p. 26 |
| Off-line Models | p. 27 |
| Introduction | p. 27 |
| Detailed Nonlinear Static Modelling | p. 28 |
| Detailed Nonlinear Dynamic Modelling | p. 30 |
| Relationship Between Static and Dynamic Models | p. 31 |
| Dynamic Characteristic Models | p. 33 |
| Deriving the Dynamic Characteristic Model | p. 33 |
| Graphical Representation | p. 35 |
| Dynamic Characteristic in Reduced Parameters | p. 35 |
| Interpolation Between Operating Points | p. 37 |
| Linear Dynamic Models | p. 39 |
| Obtaining Linear Dynamic Models | p. 40 |
| Estimation of LDM Parameters Using Detailed Static Model | p. 40 |
| Accounting for Additional Gas Flow Dynamics | p. 43 |
| Twin-shaft Turbo Jet Example | p. 44 |
| Concluding Remarks | p. 46 |
| On-line Models | p. 47 |
| Introduction | p. 47 |
| Conflicting Requirements of Simplicity, Speed and Accuracy | p. 47 |
| Stages of Building RPLDM | p. 49 |
| Combination of Static Line and Set of Linear Models | p. 49 |
| LDM at the Nearest Static Point | p. 50 |
| Piecewise Linear Approximation of the Static Line | p. 51 |
| Operating Parameter and Perpendicular to Static Line | p. 53 |
| Piecewise Linear Approximation of LDM Parameters | p. 55 |
| Example of Turbo Jet Modelling | p. 59 |
| Accounting for Atmospheric Conditions of Engine Operation | p. 60 |
| Concluding Remarks | p. 62 |
| Gas Turbine System Identification | |
| Linear System Identification | p. 65 |
| Introduction | p. 65 |
| Linear Models | p. 65 |
| Model Estimation | p. 68 |
| Time-Domain | p. 68 |
| Frequency-Domain | p. 71 |
| Model Order Selection and Validation | p. 76 |
| Comparison of Models and Approaches | p. 78 |
| Experiment Design | p. 79 |
| Input Signals | p. 81 |
| Analysing Periodic Data | p. 85 |
| Concluding Remarks | p. 88 |
| Linear Gas Turbine Modelling | p. 89 |
| Introduction | p. 89 |
| Gas Turbine Testing | p. 89 |
| Test Signal Designs | p. 91 |
| Nonparametric Analysis | p. 91 |
| Synchronisation | p. 91 |
| Drift and Repeatability | p. 92 |
| Noise and Nonlinearities | p. 93 |
| Frequency Response Functions | p. 96 |
| Frequency-Domain Estimation | p. 97 |
| High-Pressure Shaft | p. 100 |
| Low-Pressure Shaft | p. 101 |
| Models at Different Operating Points | p. 104 |
| Low-Frequency Mode | p. 105 |
| Influence of Engine Nonlinearity | p. 105 |
| Time-Domain Estimation | p. 108 |
| High-Pressure Shaft | p. 108 |
| Low-Pressure Shaft | p. 109 |
| Time- Versus Frequency-Domain | p. 112 |
| Comparison with Thermodynamic Models | p. 115 |
| Concluding Remarks | p. 116 |
| Closed-Loop Control and System Identification | p. 117 |
| Introduction | p. 117 |
| Concept of Closed-Loop Identifiability | p. 117 |
| Existing Approaches to Closed-Loop Identifiability | p. 119 |
| Parametric Identifiability | p. 120 |
| Nonparametric Identifiability | p. 121 |
| Common Features of Parametric and Nonparametric Identifiability | p. 122 |
| Summary of Identifiability Concepts | p. 123 |
| Example of Closed-Loop Identifiability Analysis | p. 123 |
| Relationship Between Identifiability and Distribution Function | p. 126 |
| Identifiability Monitoring via Asymmetry and Excess Analysis | p. 127 |
| Identifiability Monitoring via Comparison of a priori Models with Estimates | p. 128 |
| Identifiability and Instrumental Variable Method | p. 128 |
| Concluding Remarks | p. 130 |
| Nonlinear Gas Turbine Modelling | p. 131 |
| Introduction | p. 131 |
| Nonlinear System Representation | p. 131 |
| Functional Representations | p. 132 |
| Block-Structured Systems | p. 133 |
| The Polynomial NARMAX Approach | p. 134 |
| Feedforward Neural Network Models | p. 136 |
| Local Approximations | p. 136 |
| Nonlinear System Identification | p. 137 |
| Nonlinear Gas Turbine Modeling Using NARMAX Structures | p. 139 |
| Parameter Estimation | p. 139 |
| Structure Selection | p. 143 |
| Model Validation | p. 146 |
| A Proposed Identification Scheme | p. 148 |
| Gas Turbine Modelling | p. 149 |
| Nonlinear Gas Turbine Modeling Using Neural Network Models | p. 151 |
| Multilayer Perceptron Neural Networks | p. 151 |
| Gas Turbine Modelling Using Multilayer Perceptron Neural Networks | p. 153 |
| Concluding Remarks | p. 155 |
| New Perspectives in Modelling, Identification, Condition Monitoring and Control | |
| Nonlinear Model Structure Selection Using Evolutionary Optimisation Methods | p. 159 |
| Introduction | p. 159 |
| Genetic Algorithms and Genetic Programming | p. 159 |
| Genetic Algorithms | p. 160 |
| Genetic Algorithm Operators | p. 161 |
| Genetic Programming | p. 162 |
| Genetic Programming Operators | p. 163 |
| Multiobjective Optimisation | p. 165 |
| Pareto-ranking Method | p. 166 |
| Example of Engine Model Structure Selection Using Genetic Programming | p. 167 |
| Description of the Engine System | p. 168 |
| Result Analysis | p. 168 |
| Concluding Remarks | p. 176 |
| System Identification Using Frequency Response Techniques with Optimal Spectral Resolution | p. 177 |
| Introduction | p. 177 |
| Problem Formulation | p. 178 |
| Spectral Estimation | p. 179 |
| Spectral Analysis Calculations | p. 181 |
| Mean Value | p. 181 |
| Correlation Functions | p. 182 |
| Spectral Density | p. 183 |
| Spectral Windowing | p. 183 |
| Frequency Response and Coherence | p. 186 |
| Errors of FRF Estimation by Spectral Methods | p. 186 |
| Spectral Estimation Bias | p. 187 |
| Spectral Estimation Variance | p. 188 |
| Optimal Spectral Resolution | p. 192 |
| Graphical Interpretation | p. 193 |
| Optimum Spectral Resolution And Wavelets | p. 194 |
| Concluding Remarks | p. 195 |
| Turbo Prop Fan Engine Identification: Practical Issues | p. 197 |
| Introduction | p. 197 |
| Turbo Prop Fan Identification | p. 197 |
| Description of Experiment | p. 197 |
| Plant Decomposition | p. 199 |
| Identification of Fuel Metering System | p. 199 |
| Identification of Shaft Speed Dynamics | p. 203 |
| Identification of Compressor Pressure Dynamics | p. 204 |
| Identification of Turbine Temperature Dynamic Model | p. 206 |
| Identification of VSV Actuators in LP And HP Compressors | p. 207 |
| Identification of Step Drives in Prop Fan Controller | p. 211 |
| Identification of Prop Fan Dynamics | p. 212 |
| Closed-Loop Identifiability Analysis | p. 214 |
| Concluding Remarks | p. 215 |
| Stochastic Gas Turbine Engine Models | p. 217 |
| Introduction | p. 217 |
| Disturbances Affecting Control Systems of Aero Engines | p. 217 |
| Applications of Stochastic Modelling in Aero Engine Control | p. 218 |
| Signal Filtering | p. 218 |
| Identification for Control Systems Design and Condition Monitoring | p. 219 |
| Optimal Control of Power Plant | p. 220 |
| Stochastic Simulation in Control Systems Design and Testing | p. 221 |
| Markov Modelling of Dynamic Systems | p. 222 |
| Basic Definitions | p. 222 |
| Markov Chain Representation of Dynamic Systems | p. 223 |
| Basic Descriptive Properties | p. 226 |
| Probability Density Function | p. 226 |
| Mean Value | p. 227 |
| Correlation Function | p. 227 |
| Parameters of Autoregression Model | p. 227 |
| Identification of Markov Chains | p. 228 |
| Fuzzy Markov Chains | p. 229 |
| Concluding Remarks | p. 232 |
| Markov Modelling of Turbo Prop Fan | p. 233 |
| Introduction | p. 233 |
| Experimentation with Turbo Prop Fan | p. 233 |
| Identification of Gas Turbine Dynamics | p. 234 |
| Simulation of Random Environment in HIL Tests of Digital Controllers | p. 238 |
| Markov Simulation Technique | p. 239 |
| Modelling of Inlet Pressure and Temperature with Markov Chains | p. 240 |
| Hardware-in-the-Loop Simulation Using Stochastic Models | p. 241 |
| Markov Modelling in Condition Monitoring of Aero Engines | p. 244 |
| Model-Based Approach to Condition Monitoring | p. 245 |
| Condition Monitoring in Dual-Lane Control | p. 245 |
| Simulation Results | p. 249 |
| Concluding Remarks | p. 249 |
| Optimal Control of Gas Turbine Engines Using Mathematical Programming | p. 251 |
| Introduction | p. 251 |
| Optimization of Engine Performance Through Optimal Control | p. 251 |
| Problem Formulation | p. 253 |
| Algorithm for Real-Time Resolution of a Quadratic Programming Problem | p. 256 |
| Example of Turbo Jet Control, Optimal by Speed | p. 259 |
| Example of Turbo Jet Control, Optimal by Specific Fuel Consumption | p. 261 |
| Concluding Remarks | p. 270 |
| Dynamic Model Identification of a Turbo Jet Engine | p. 271 |
| Introduction | p. 271 |
| Static Modelling Techniques | p. 271 |
| Parametric Dynamic Modelling Techniques | p. 273 |
| Static Model Identification | p. 275 |
| Mean Values | p. 275 |
| "Three-Level" Test | p. 275 |
| Comparison with Previous Series of Tests | p. 277 |
| Notes Regarding Fuel Feed System | p. 278 |
| Dynamic Model Identification | p. 279 |
| Multisine Test | p. 279 |
| Open-Loop Identification with No Test Signal | p. 281 |
| Closed-Loop Identification with No Test Signal | p. 286 |
| Concluding Remarks | p. 292 |
| References | p. 293 |
| Index | p. 305 |
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