Small-signal stability analysis for the multi-terminal VSC MVDC distribution network; a review

Abstract

The stable operation and control of the proposed terrestrial multi-terminal Voltage Source Converter (VSC) medium voltage DC (MVDC) distribution network is a remarkable motivation towards developing the future universal DC grid interconnecting the low voltage DC systems on one side and the high voltage DC systems on the other. The small-signal stability analysis are important in designing these power electronic based systems (PEBS). In this study, small-signal stability approaches for PEBS are reviewed with the aim of identifying suitable methods for the proposed MVDC distribution network. It is established that the impedance-based methods are suitable for local stability analysis complementing very well with the state-space modelling-eigenvalue analysis method best for global stability analysis. The Lyapunov linearisation method offers simple, adaptable, and accurate small-signal and large-signal stability study. On the other hand, the bifurcation analysis is an emerging non-linear approach with promising efficiency and precision. In conclusion, there is no single small-signal stability criterion that encompass an acceptable level of accuracy, adaptability, and efficiency. Thus, the impedance-based methods combined with state-space modelling-eigenvalue analysis, Lyapunov linearisation, and bifurcation theory can be suitable small-signal stability approaches for the multi-terminal MVDC distribution network.

Keywords

• power grids
• bifurcation
• stability
• eigenvalues and eigenfunctions
• power system stability
• power electronics
• distributed power generation
• fault location
• Lyapunov methods
• power distribution protection
• small-signal stability analysis
• multiterminal VSC MVDC distribution network
• stable operation
• terrestrial multiterminal
• medium voltage DC distribution network
• future universal DC grid
• power electronic based systems
• PEBS
• impedance-based methods
• local stability analysis
• state-space modelling-eigenvalue analysis method
• global stability analysis
• Lyapunov linearisation method
• accurate small-signal
• large-signal stability study
• bifurcation analysis
• single small-signal stability criterion
• suitable small-signal stability approaches
• multiterminal MVDC distribution network
• low-voltage DC systems
• high-voltage DC systems