TB 222 2003 SC B4 WG B4.05 On voltage and power stability in AC/DC systems

Significant new results concerning the definitions of voltage and power stability on AC/DC systems.

 Download TB from ecigre website 




1 BasicTheory and Definitions

      1.1 Introduction

      1.2 Simplified Explanation of Power/Voltage Instability Phenomenon

      1.3 Definitions of Voltage Stability in AC Power Systems

            1.3.1 Definitions According to CIGRE

            1.3.2 Definitions According to IEEE

            1.3.3 Other Definitions

            1.3.4 Discussion of CIGRE and IEEE Definitions

      1.4 Analysis of AC/DC Systems

            1.4.1 Maximum Power Curves

            1.4.2 Voltage Sensitivity Factors

      1.5 Definitions for AC/DC Systems

      1.6 Discussion

 2 Analytical Tools and Methods 

      2.1 Introduction

      2.2 Power Stability

            2.2.1 Maximum Available Power

            2.2.2 Maximum Power Curve

      2.3 Voltage Stability

            2.3.1 Voltage Sensitivity

      2.4 Control Stability

            2.4.1 Control Sensitivity Index

            2.4.2 CSI Computation

      2.5 Extension to Higher-Order Models

            2.5.1 Maximum Power

            2.5.2 Voltage Sensitivity

      2.6 Incorporation of Local Devices

            2.6.1 Loads

            2.6.2 Other Devices

      2.7 Relationship Between Power and Voltage Stability Methods

      2.8 Appendix: Definition of ESCR

 3 Comparison of MPC with Detailed Simulations

      3.1 Simulations Using a Simplified Model

      3.2 Inclusion of a Synchronous Compensator at the Converter Bus

            3.2.1 Differences Arising from Neglecting the Zero-Power Constraint for the Synchronous


            3.2.2 Comparison with a Detailed Machine Model with and without Excitation Control

            3.2.3 Inclusion of Controlled Excitation

      3.3 Conclusions

      3.4 Appendix: Equations used in MPC Calculations

 4 Influence of System Operating Conditions and Converter Design

      4.1 Effect of Load Modeling on the MAP and AC Voltage

      4.2 Effect of a Parallel AC Line

      4.3 Effect of Tap Changing

      4.4 MPC for Capacitor Commutated Converters

      4.5 Conclusions

 5 Multi-Infeed HVDC Systems 55

      5.1 Development in the Study of Multi-Infeed HVDC Systems

      5.2 System Models

      5.3 Analysis of Voltage/Power Stability of Multi-Infeed HVDC Systems

 6 Planning and Analysis of Systems - Principles and Concepts

      6.1 Background

      6.2 Simplified Explanation of Power/Voltage Instability Phenomenon1

      6.3 “Weak-Connection” Versus “Weak-System” In-Feed of a DC Link