book

Power System Operation and Control

by S. Sivanagaraju, G. Sreenivasan

July 2009

Intermediate to advanced

606 pages

15h 36m

English

Pearson India

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1.1 Introduction1.2 Load Curve1.3 Load–Duration Curve1.4 Integrated Load–Duration Curve1.4.1 Uses of Integrated Load–Duration Curve1.5 Definition of Terms and Factors1.5.1 Connected Load1.5.2 Maximum Demand1.5.3 Demand Factor1.5.4 Average Load1.5.5 Load Factor1.5.6 Diversity Factor1.5.7 Plant Capacity1.5.8 Plant Capacity Factor1.5.9 Utilization Factor (or Plant-Use Factor)1.5.10 Firm Power1.5.11 Prime Power1.5.12 Dump Power1.5.13 Spill Power1.5.14 Cold Reserve1.5.15 Hot Reserve1.5.16 Spinning Reserve1.6 Base Load and Peak Load on a Power Station1.7 Load Forecasting1.7.1 Purpose of Load Forecasting1.7.2 Classification of Load Forecasting1.7.3 Forecasting ProcedureKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
2.1 Introduction2.2 Characteristics of Power Generation (Steam) Unit2.3 System Variables2.3.1 Control Variables (PG and QG)2.3.2 Disturbance Variables (PD and QD)2.3.3 State Variables (V and δ)2.4 Problem of Optimum Dispatch—Formulation2.5 Input–Output Characteristics2.5.1 Units of Turbine Input2.6 Cost Curves2.7 Incremental Fuel Cost Curve2.8 Heat Rate Curve2.9 Incremental Efficiency2.10 Non-Smooth Cost Functions with Multivalve Effect2.11 Non-smooth Cost Functions with Multiple Fuels2.12 Characteristics of a Hydro-Power Unit2.12.1 Effect of the Water Head on Discharge of Water for a Hydro-Unit2.12.2 Incremental Water Rate Characteristics of Hydro-Units2.12.3 Incremental Cost Characteristic of a Hydro-Unit2.12.4 Constraints of Hydro-Power Plants2.13 Incremental Production Costs2.14 Classical Methods for Economic Operation of System Plants2.15 Optimization Problem—Mathematical Formulation (Neglecting the Transmission Losses)2.15.1 Objective Function2.15.2 Constraint Equations2.16 Mathematical Determination of Optimal Allocation of Total Load Among Different Units2.17 Computational Methods2.17.1 Analytical Method2.17.2 Graphical Method2.17.3 Solution by Using a Digital Computer2.18 Economic Dispatch Neglecting Losses and Including Generator Limits2.19 Flowchart for Obtaining Optimal Scheduling of Generating Units by Neglecting the Transmission Losses2.20 Economical Load Dispatch—In Other Units2.20.1 Nuclear units2.20.2 Pumped storage hydro-units2.20.3 Hydro-plants2.20.4 Including reactive-power flowsKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
3.1 Introduction3.2 Optimal Generation Scheduling Problem: Consideration of Transmission Losses3.2.1 Mathematical modeling3.3 Transmission Loss Expression in Terms of Real-Power Generation—Derivation3.4 Mathematical Determination of Optimum Allocation of Total Load when Transmission Losses are Taken into Consideration3.4.1 Determination of ITL formula3.4.2 Penalty Factor3.5 Flowchart for the Solution of an Optimization Problem when Transmission Losses are ConsideredKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems

4.1 Introduction4.2 Comparison with Economic Load Dispatch4.3 Need for UC4.4 Constraints in UC4.4.1 Spinning Reserve4.4.2 Thermal Unit Constraints4.4.3 Hydro-Constraints4.4.4 Must Run4.4.5 Fuel Constraints4.5 Cost Function Formulation4.5.1 Start-up Cost Consideration4.5.2 Shut-down Cost Consideration4.6 Constraints for Plant Commitment Schedules4.7 Unit Commitment—Solution Methods4.7.1 Enumeration Scheme4.7.2 Priority-list Method4.7.3 Dynamic Programming4.8 Consideration of Reliability in Optimal UC Problem4.8.1 Patton's security function4.9 Optimal UC with Security Constraint4.9.1 Illustration of Security Constraint with Example 4.24.10 Start-Up ConsiderationKey NotesMultiple-Choice QuestionsShort Questions and AnswersReview QuestionsProblems
5.1 Introduction5.2 Optimal Power-Flow Problem without Inequality Constraints5.2.1 Algorithm for Computational Procedure5.3 Optimal Power-Flow Problem with Inequality Constraints5.3.1 Inequality Constraints on Control Variables5.3.2 Inequality Constraints on Dependent Variables—Penalty Function MethodKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview Questions
6.1 Introduction6.2 Hydro-Thermal Co-ordination6.3 Scheduling of Hydro-Units in a Hydro-Thermal System6.4 Co-ordination of Run-off River Plant and Steam Plant6.5 Long-Term Co-ordination6.6 Short-Term Co-ordination6.6.1 Constant Hydro-Generation Method6.6.2 Constant Thermal Generation Method6.6.3 Maximum Hydro-Efficiency Method6.7 General Mathematical Formulation of Long-Term Hydro-Thermal Scheduling6.7.1 Solution of Problem-Discretization Principle6.7.2 Solution Technique6.7.3 Algorithm6.8 Solution of Short-Term Hydro-Thermal Scheduling Problems—Kirchmayer's Method6.9 Advantages of Operation of Hydro-Thermal Combinations6.9.1 Flexibility6.9.2 Greater Economy6.9.3 Security of Supply6.9.4 Better Energy Conservation6.9.5 Reserve Capacity MaintenanceKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
7.1 Introduction7.2 Necessity of Maintaining Frequency Constant7.3 Load Frequency Control7.4 Governor Characteristics of a Single Generator7.5 Adjustment of Governor Characteristic of Parallel Operating Units7.6 LFC: (P–f Control)7.7 Q–V Control7.8 Generator Controllers (P–f and Q–V Controllers)7.9 P–f Control versus Q–V Control7.10 Dynamic Interaction Between P–f and Q–V Loops7.11 Speed-Governing System7.11.1 Speed-Governing System Model7.12 Turbine Model7.12.1 Non-reheat-type Steam Turbines7.12.2 Incremental or Small Signal for a Turbine-Governor System7.12.3 Reheat Type of Steam Turbines7.13 Generator-Load Model7.14 Control Area Concept7.15 Incremental Power Balance of Control Area7.16 Single Area Identification7.16.1 Block Diagram Representation of a Single Area7.17 Single Area—Steady-State Analysis7.17.1 Speed-Changer Position is Constant (Uncontrolled Case)7.17.2 Load Demand is Constant (Controlled Case)7.17.3 Speed Changer and Load Demand are Variables7.18 Static Load Frequency Curves7.19 Dynamic Analysis7.20 Requirements of the Control Strategy7.20.1 Integral Control7.21 Analysis of the Integral Control7.22 Role of Integral Controller Gain (KI) Setting7.23 Control of Generator Unit Power OutputKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
8.1 Introduction8.2 Composite Block Diagram of a Two-Area Case8.3 Response of a Two-Area System—Uncontrolled Case8.3.1 Static Response8.3.2 Dynamic Response8.4 Area Control Error —Two-Area Case8.5 Composite Block Diagram of a Two-Area System (Controlled Case)8.5.1 Tie-line Bias Control8.5.2 Steady-State Response8.5.3 Dynamic Response8.6 Optimum Parameter Adjustment8.7 Load Frequency and Economic Dispatch Controls8.8 Design of Automatic Generation Control Using the Kalman Method8.9 Dynamic-State-Variable Model8.9.1 Model of Single-Area Dynamic System in a State-Variable Form8.9.2 Optimum Control Index (I)8.9.3 Optimum Control Problem and Strategy8.9.4 Dynamic Equations of a Two-Area System8.9.5 State-Variable Model for a Three-Area Power System8.9.6 Advantages of State-Variable ModelKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
9.1 Introduction9.2 Objectives of Load Compensation9.2.1 P. f. Correction9.2.2 Voltage Regulation Improvement9.2.3 Load Balancing9.3 Ideal Compensator9.4 Specifications of Load Compensation9.5 Theory of Load Compensation9.5.1 P. f. correction9.5.2 Voltage Regulation9.6 Load Balancing and p.f. Improvement of Unsymmetrical Three-Phase Loads9.6.1 P. f. Correction9.6.2 Load Balancing9.7 Uncompensated Transmission Lines9.7.1 Fundamental Transmission Line Equation9.7.2 Characteristic Impedance9.7.3 Surge Impedance or Natural Loading9.8 Uncompensated Line with Open-Circuit9.8.1 Voltage and Current Profiles9.8.2 The Symmetrical Line at no-Load9.8.3 Underexcited Operation of Generators Due to Line-Charging9.9 The Uncompensated Line Under Load9.9.1 Radial line with fixed Sending-end Voltage9.9.2 Reactive Power Requirements9.9.3 The Uncompensated Line Under Load with Consideration of Maximum Power and Stability9.10 Compensated Transmission Lines9.11 Sub-Synchronous Resonance9.11.1 Effects of Series and Shunt Compensation of Lines9.11.2 Concept of SSR in Lines9.12 Shunt Compensator9.12.1 Thyristor-Controlled Reactor9.12.2 Thyristor-Switched Capacitor9.13 Series Compensator9.14 Unified Power-Flow Controller9.15 Basic Relationship for Power-Flow Control9.15.1 Without Line Compensation9.15.2 With Series Capacitive Compensation9.15.3 With Shunt Compensation9.15.4 With Phase Angle Control9.16 Comparison of Different Types of Compensating Equipment for Transmission Systems9.17 Voltage Stability—What is it?9.17.1 Voltage Stability9.17.2 Voltage Collapse9.18 Voltage-Stability Analysis9.18.1 P–V Curves9.18.2 Concept of Voltage Collapse Proximate Indicator9.18.3 Voltage-Stability Analysis: Q–V Curves9.19 Derivation for Voltage-Stability IndexKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
10.1 Introduction10.2 Necessity of Voltage Control10.3 Generation and Absorption of Reactive Power10.4 Location of Voltage-Control Equipment10.5 Methods of Voltage Control10.5.1 Excitation Control10.5.2 Shunt Capacitors and Reactors10.5.3 Series Capacitors10.5.4 Tap-Changing Transformers10.5.5 Booster Transformers10.5.6 Synchronous Condensers10.6 Rating of Synchronous Phase ModifierKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview QuestionsProblems
11.1 Introduction11.2 Hydraulic Turbine System11.2.1 Modeling of Hydraulic Turbine11.3 Steam Turbine Modeling11.3.1 Non-reheat Type11.3.2 Reheat type11.4 Synchronous Machines11.4.1 Salient-pole-type Rotor11.4.2 Non-salient-pole-type Rotor11.5 Simplified Model of Synchronous Machine (Neglecting Saliency and Changes in Flux Linkages)11.6 Effect of Saliency11.7 General Equation of Synchronous Machine11.8 Determination of Synchronous Machine Inductances11.8.1 Assumptions11.9 Rotor Inductances11.9.1 Rotor Self-Inductance11.9.2 Stator to Rotor Mutual Inductances11.10 Stator Self-Inductances11.11 Stator Mutual Inductances11.12 Development of General Machine Equations—Matrix Form11.13 Blondel's Transformation (or) Park's Transformation to ‘dqo’ Components11.14 Inverse Park's Transformation11.15 Power-Invariant Transformation in ‘f-d-q-o’ Axes11.16 Flux Linkage Equations11.17 Voltage Equations11.18 Physical Interpretation of Equations (11.62) and (11.68)11.19 Generalized Impedance Matrix (Voltage–Current Relations)11.20 Torque Equation11.21 Synchronous Machine—Steady-state Analysis11.21.1 Salient-pole Synchronous Machine11.21.2 Non-salient-pole Synchronous (Cylindrical Rotor) Machine11.22 Dynamic Model of Synchronous Machine11.22.1 Salient-pole Synchronous Generator—Sub-Transient Effect11.22.2 Dynamic Model of Synchronous Machine Including Damper Winding11.22.3 Equivalent Circuit of Synchronous Generator—Including Damper Winding Effect11.23 Modeling of Synchronous Machine—Swing EquationKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview Questions
12.1 Introduction12.2 Modeling of Speed-Governing Systems12.3 For Steam Turbines12.3.1 Mechanical–Hydraulic-Controlled Speed-Governing Systems12.3.2 Electro–Hydraulic-Controlled Speed-Governing Systems12.3.3 General Model for Speed-Governing Systems12.4 For Hydro-Turbines12.4.1 Mechanical–Hydraulic-Controlled Speed-Governing Systems12.4.2 Electric–Hydraulic-Controlled Speed-Governing System12.5 Modeling with Limits12.5.1 Wind-up Limiter12.5.2 Non-wind-up Limiter12.6 Modeling of a Steam-Governor Turbine System12.6.1 Reheat System Unit12.6.2 Block Diagram Representation12.6.3 Transfer Function of the Steam-Governor Turbine Modeling12.7 Modeling of a Hydro-Turbine-Speed Governor12.8 Excitation Systems12.9 Effect of Varying Excitation of a Synchronous Generator12.9.1 Explanation12.9.2 Limitations of Increase in Excitation12.10 Methods of Providing Excitation12.10.1 Common Excitation Bus Method12.10.2 Individual Excitation Method12.10.3 Block Diagram Representation Structure of a General Excitation System12.11 Excitation Control Scheme12.12 Excitation Systems—Classification12.12.1 DC Excitation System12.12.2 AC Excitation System12.12.3 Static Excitation System12.13 Various Components and their Transfer Functions of Excitation Systems12.13.1 PT and Rectifier12.13.2 Voltage Comparator12.13.3 Amplifiers12.14 Self-excited Exciter and Amplidyne12.15 Development of Excitation System Block Diagram12.15.1 Transfer Function of the Stabilizing Transformer12.15.2 Transfer Function of Synchronous Generator12.15.3 IEEE Type-1 Excitation System12.15.4 Transfer Function of Overall Excitation System12.16 General Functional Block Diagram of an Excitation System12.16.1 Terminal Voltage Transducer and Load Compensation12.16.2 Exciters and Voltage Regulators12.16.3 Excitation System Stabilizer and Transient Gain Reduction12.16.4 Power System Stabilizer12.17 Standard Block Diagram Representations of Different Excitation Systems12.17.1 DC Excitation System12.17.2 AC Excitation System12.17.3 Static Excitation SystemKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview Questions
13.1 Introduction13.2 The Concept of System Security13.2.1 Long-Term Planning13.2.2 Operational Planning13.2.3 On-line Operation13.3 Security Analysis13.3.1 Digital Simulation13.3.2 Hybrid Computer Simulation13.3.3 Lyapunov Methods13.3.4 Pattern Recognition13.4 Security Enhancement13.5 SSS Analysis13.5.1 Requirements of an SSS Assessor13.6 Transient Security Analysis13.6.1 Digital Simulation13.6.2 Pattern Recognition13.6.3 Lyapunov Method13.7 State Estimation13.7.1 State Estimator13.7.2 Static-State Estimation13.7.3 Modeling of Uncertainty13.7.4 Some Basic Facts of State Estimation13.7.5 Least Squares Estimation13.7.6 Applications of State EstimationKey NotesShort Questions and AnswersMultiple-Choice QuestionsReview Questions

Overview

Power System Operation and Control is a comprehensive text designed for undergraduate and postgraduate courses in electrical engineering. This book aims to meet the requirements of electrical engineering students of universities all over India. This text is written in a simple and easy-to-understand manner and is valuable both as a textbook as well as a reference book for engineering students and practicing engineers.