# FEASIBILITY OF USING BATTERY ENERGY STORAGE SYSTEMS FOR FREQUENCY STABILIZATION IN INTEGRATED POWER SYSTEMS WITH POWERFUL SOLAR POWER PLANTS

• M. Kulyk Institute of General Energy of the National Academy of Sciences of Ukraine
• I. Dryomin Advanced Analytics and Data Science S.R.O.
• O. Zgurovets

### Abstract

Current trends in the development of electric-power industry point to an increase in the part of renewable energy in the total energy balance. The annual increase in total installed capacity of SPPs is more than 32%. The introduction of large volumes of such power into the power system may cause a deterioration of the quality of electricity, stability of the power system, and rise of emergency situations. This problem can be solved with the help of new energy storage systems based on batteries, which, due to their high power and operating speed, make it possible to consider them as a means of frequency stabilization for compensating changes in SPP power. In this paper, we consider the process of frequency and power regulation in integrated power systems where powerful SPP and BESS work simultaneously. For these investigations we developed mathematical model that consists of the general power balance equation, equations describing the operation of all generators, electrical load and losses, as well as constraints and initial conditions. The resulting model enables one to study the features of frequency and power regulation processes when BESS and SPP work together under various conditions and characteristics of system elements as well as to determine the most efficient control laws. The calculations were carried out for an aggregated power system, including nuclear, thermal, hydroelectric power plants, load, losses, solar power plant and battery energy storage system. In the study performed, we modeled the mode of operation of the power system where it was unregulated for 2 s, in other words, SPP and other elements of the system worked, except for BESS. During such work, a significant frequency deviation (more than 1,1 Hz) was observed. Starting from 2 s and further, the battery was switched on. In the course of operation, the battery for 9 seconds stabilized frequency at level of 50 Hz with a deviation less than 0,01 Hz and ensured it at this level throughout the entire interval to 400 s. The results obtained show that the use of large SPP combined with BESS of comparable power makes it possible to achieve frequency control accuracy at a level that meets the regulatory requirements of the power systems of Ukraine and European Union.

### References

1. Renewables 2018: Global Status Report. REN21. URL: http://www.ren21.net/wp-content/uploads/2018/06/17-8652_GSR2018_FullReport_web_final_.pdf (Last accessed: 30.08.2018).
2. Renewables briefly cover 100% of Germany's power de-mand for 2nd time. Clean Energy Wire. URL: https://www.cleanenergywire.org/news/renewables-briefly-cover-100-germanys-power-demand-2nd-time (Last accessed: 30.08.2018).
3. Renewables 2017: Global Status Report. REN21. URL: http://www.ren21.net/wp-content/uploads/2017/06/170607_GSR_2017_Full_Report.pdf (Last accessed: 30.08.2018).
4. Informatsiia shchodo potuzhnosti ta obsiahiv vyrobny-tstva elektroenerhii ob’iektamy vidnovliuvanoi elektroenerhetyky, yakym vstanovleno «zelenyi» taryf (stanom na 31.03.2018). Derzhavne ahentstvo z enerhoefektyvnosti ta enerhozberezhennia Ukrainy. URL: http://saee.gov.ua/sites/default/files/Information %20RES%20in%20Ukraine%20%20Q1%202018.pdf (Last ac-cessed: 30.08.2018) (Ukr.).
5. Vyznachennia hranychnykh obsiahiv, umov i rezhymiv vykorystannia vitrovykh ta soniachnykh elektrostantsii u skladi obiednanoi enerhosystemy Ukrainy. (2015). Zvit pro naukovo-doslidnu robotu. DR № 0113U004085. K.: Instytut zahalnoi ener-hetyky NAN Ukrainy,. S. 26—30 (Ukr.).
6. Kulyk, М.M., & Dryomin, I.V. (2013). General-puropse model of frequency and capacity regulation in united power systems. Problemy Zahal’noi Enerhetyky - The Prob-lems of General Energy, 4 (35). 5—15 (Ukr.).
7. Kulyk, М.M., & Dryomin, I.V. (2015). Generalized mathematical model and features of adaptive automatic fre-quency and power control systems. Problemy Zahal’noi Ener-hetyky - The Problems of General Energy, 4 (43). 14—23 (Ukr.). https://doi.org/10.15407/pge2015.04.014
8. Electricity and Energy Storage (Updated May 2018). World Nuclear Assotiation. URL: http://www.world-nuclear.org/information-library/current-and-future-generation/electricity-and-energy-storage.aspx (Last accessed: 01.06.2018).
9. Javier Marcos, Luis Marroyo, Eduardo Lorenzo, David Alvira, Eloisa Izco. Power output fluctuations in large scale PV plants: one year observations with one second resolution and a derived analytic model. Progress in Photovoltaics: Research and Applications. 2011. Volume 19, Issue 24.

Abstract views: 125