Scientific principles, methods and techniques to reduce the impact of low-frequency oscillations in the power modes of the United Power System

Analysis of accidents in electric power systems (EPS) of the world has shown that one of the reasons for their occurrence is poor damped low-frequency oscillations (LFO). This requires solving of the complex problem aimed to reduce the LFO impact and increase the stability of the EPS. For the interconnected power system (IPS) of Ukraine, which is characterized by relatively weak interconnections in the conditions of rising of amount of distributed energy sources (RES) to solve these problems it is particularly important.

As a result of theoretical and experimental studies it was developed the scientific concept of the origin of the IPS LFO. It was proposed the novel methods for the identification of the dominant LFO based on the processing of synchronized measurements if the wide area monitoring systems (WAMS). It was developed the technique of experimental research and mathematical modeling of low-frequency oscillations of the interconnected power system for quasi-steady-state and transient modes with renewable energy sources, and discovered the effect of setting the frequency control systems. It was proposed the method for identifying a dynamic model of IPS on the basis of the analysis of the motion of coherent groups of generators inertia centers (CGG), which allowed using passive experiment data, get an IPS model EEC, taking into account the mutual influence of the CGG EPS mode. It was proposed a comprehensive approach to building a real-time monitoring and damping systems by parametric frequency synthesis and power control systems with the use of flexible alternating current transmission (FACTS). In work it was determined the new results that explain the dynamic properties of IPS, in enacting systemic stabilizers, damping quality assessment carried out by using FACTS. As a result it was formed the recommendations on the selection and placement requirements for stabilizers in the IPS and requirements for information transfer from WAMS devices for monitoring of electrical power systems in real time.