An important aspect of power system safety is the stability of the voltage.
Continual assessment of voltage stability is vital to the safety of the power system, which is why several online methods for analysing voltage stability have been proposed. This concern has led to the development of several online voltage stability analysis methods. This concept of impedance matching based on the Thevenin equivalent has attracted considerable interest among the indices. However, there have been reports that the traditional impedance match does not perform as expected in multiple-load power systems.
The Banach fixed-point theorem is used in this paper to propose a new approach to voltage stability assessment. Doing so can develop a real-time voltage stability monitoring scheme without estimating voltage stability analysis parameters. It was demonstrated that the derived method could be applied to a 5-generator and 18-bus system using time-domain dynamic simulations. Phasor measurement units can also be applied to an entire power system.
Several studies have been conducted on voltage stability in the power system at home and abroad. A summary and comparison of the power system’s definition and classification of voltage stability are provided. Then the static and dynamic voltage instability mechanisms are explained and analysed from both aspects.
The present research situation of static voltage stability analysis and dynamic voltage stability analysis in power system voltage stability is summarised and reviewed in this paper, as well as the current research status of both of these analysis methods. In addition, future development trends will be discussed. For a system to maintain a voltage within a suitable range when faced with disturbances, such as a small rise in the load, it has to have the ability to do so.
Both load characteristics and continuous and discontinuous control influences affect small disturbance voltage stability. When experiencing disturbances such as losing the generator, a short circuit, a line outage, or a system failure, large disturbance voltage stability is referred to as maintaining the bus voltage within a safe range during these situations.
The stability of large disturbance voltage can be determined by the characteristics of the system, the load characteristics, and the control and protection of all of these factors combined. Depending on the time and duration of the period and duration of the voltage stability, it is possible to distinguish between long- and short-term voltage stability.
Long-term voltage stability typically lasts for several minutes to dozens of minutes. This situation generally depends on factors such as a generator excitation current limiter, transformer tap adjustment, etc. In general, short-term voltage stability is of shorter duration, ranging from a few seconds to several minutes, and is primarily related to HVDC converters and induction motors.