清华大学动态电力系统课件（英文版）6.ppt

动态电力系统 张 毅 威 ywzhang@ 西主楼 III-210 电话Ftp：0 11.1.5 Fundamentals of Automatic Generation Control AGC in isolated power system: AGC in interconnected power system 11.2 Reactive power and voltage control Objectives of voltage control and reactive power control: For each equipment, |?V| ? Enhance stability Reduce RI2 and XI2 for active power transfer. Problem: What are the main difference of frequency control and voltage control ? 11.2.1 Production and Absorption of Reactive Power Synchronous generators Problem:What limits the production and absorption of generator’s reactive power? Overhead lines Problem: When they produce or absorb reactive power? Underground cables Problem: Why it always produce reactive power? Transformers Problem: Why it always absorb reactive power? Loads Problem: What is called loads? Compensation devices Problem: 11.2.2 Methods of voltage control At all level 11.2.3 Shunt Reactors 11.2.4 Shunt Capacitors 11.2.5 Series Capacitors 11.2.6 Synchronous Condensers 11.2.7 Static Var System 11.2.8 Principle of transmission System Compensation The characteristics of long line The characteristics of line compensation 11.2.9 Modeling of Reactive Compensating Devices Modeling for load flow and dynamic simulation 11.2.10 Application of Tap-Changing Transformers to Transmission Systems Problem: What is the policy of voltage control for high/light system load? Using OPF to decide LTC setting 11.2.11 Distribution System Voltage Regulation Problem: What are the major methods? 11.2.12 Modeling of Transformer ULTC control systems 11.3 Power-Flow Analysis Procedures Power-flow: Planning of reactive power resources (also OPF) Base of stability analysis Transmission Load flow (load at substation) Distribution Load flow (load at individual locations) Problem: What is the main purpose of power-flow analysis? 11.3.1 Pre-fault Power Flows Normal system conditions Modeling considerations Load: constant P/Q Generator output wit