Security Study on Freestanding Minigrid with Multiple Rotary Energy Sources

Security Study on Minigrid


  • Titus Oluwasuji Ajewole Osun State University
  • Olakunle Olabode Bells University of Technology
  • Daniel Akinyele
  • Abraham Amole
  • Olusola Fadipe
  • Olatunde Oladepo Department of Electrical and Electronic Engineering, Osun State University, Osogbo, Nigeria
  • Hammed O. Lasisi Department of Electrical and Electronic Engineering, Osun State University, Osogbo, Nigeria


Disturbances, freestanding, multi-machine, minigrids, security, synchronism


Traditional grid has been extensively studied for system security. For freestanding renewable energy-based minigrid, a three-source stand-alone minigrid is in this study examined for system security under large disturbances. By real-time simulation, rotor responses of the generators and voltage characteristics of the buses are assessed at sudden load change and under fault condition. Post-perturbation behaviour of the system shows synchronism is not compromised by any of the generators and the bus voltage profiles remains within their pre-perturbation statutory limits. This implies that a number of rotating machine-based energy mini-sources could be interconnected into a freestanding minigrid without compromising the stability of the system. The assessment could find use in predictive and corrective compensation for stability issues in mini integrated power systems and serve as simple generic investigative approach that could be integrated into Minigrids Remedial Action Scheme or Minigrids Energy Management System for dynamic security assessment of multi-machine island minigrids.

Author Biography

Titus Oluwasuji Ajewole, Osun State University

Department of Electrical and Electronic Engineering

Senior Lecturer


Nyirenda-Jere, T., T.O. Ajewole, J. Mutale, P. Dauenhauer and A. Ambali. 2018. Microgrids: Empowering Communities and Enabling Transformation in Africa. New Partnership for African Development, Midrand, South Africa Technical Report,

Avila, N., J.P. Carvallo, B. Shaw and D.M. Kammen. 2017. The Energy Challenge in Sub-Saharan Africa: A Guide for Advocates and Policy Makers (Part 1); Generating Energy for Sustainable and Equitable Development. In: Oxfam Research Backgrounder Series, /files/oxfam-RAEL- energySSA–pt1.pdf

Baurzhan, S. and P.J. Glenn. 2017. On-grid Solar PV Versus Diesel Electricity Generation in Sub-Saharan Africa: Economics and GHG Emissions. Sustainability.

Oyekanmi, W.A., G. Radman, A.A. Babalola and T.O. Ajewole. 2014. Power System Simulation and Contingency Ranking Using Load Bus Voltage Index. In Proc. IEEE 11th International Conf. on electronic, computer and computation,

Fu, C. and A. Bose. 1999. Contingency Ranking Based On Severity Indices in Dynamic Security Analysis. IEEE Transaction on Power Systems. 14:980–986

Makarov, Y.V., P. Du, S. Lu, T.B. Nguyen, X. Guo, J.W. Burns, J.F. Gronquist and M.A. Pai. 2012. PMU-Based Wide-Area Security Assessment; Concept, Method and Implementation. IEEE Transaction on Smart Grid. 3:1325–1332

Liu, C, K. Sun, Z.H. Rather, Z. Chen, C.L. Bak, P. Thogersen and P. Lund. 2014. A Systematic Approach for Dynamic Security Assessment and the Corresponding Preventive Control Scheme Based On Decision Trees. IEEE Transaction on Power Systems. 29:717–730

Roy, A.K. and S.K. Jain. 2013. Improved Transmission Line Contingency Analysis In Power System Using Fast Decoupled Load Flow. International Journal of Advances in Engineering and Technology. 6:2159–2170

Shamar, N.K., S.P. Phulambrikar, M. Prajapati and A. Shamar. 2013. Contingency Ranking and Analysis Using Power System Analysis Toolbox (PSAT). In the Proceedings of International Conference on Recent Trends in Applied Sciences with Engineering Applications, Innovation and System Design 59–63.

Akwukwaegbu, I.O., O.C. Nosiri and E.O. Ezugwu. 2017. Voltage Stability Investigation of the Nigerian 330kv Interconnected Grid System Using Eigenvalues Method. American Journal of Engineering Research. 6:168–182

Enemuoh, F.O., T.C. Maduemeh, J.C. Onuegbu and A.E. Anazia. 2013. Prediction of Voltage Instability in Nigerian Interconnected Electric Power System Using V-Q Sensitivity Method. International Journal of Computer Engineering Research. 3:99–107

Matang1, D., M.B. Jhala and A.L. Vaghamshi. 2016. Power System Contingency Analysis Using Artificial Neural Network. International Journal of Innovative Research in Electrical, Electronic, Instrumentation and Control Engineering. 4:274–277

Sekhar, P. and S. Mohanty. 2013. Power Systems Contingency Ranking Using Newton-Raphson Load Flow Method. In the Proceedings of IEEE Indian Conference

Zarei, S.F. and M. Parniani. 2017. A Comprehensive Digital Protection Scheme for Low-Voltage Microgrids with Inverter-Based and Conventional Distributed Generations. IEEE Transaction on Power Delivery. 32:441–452

Sortomme, E., S.S. Venkata and J. Mitr. 2010. Microgrid Protection Using Communication-Assisted Digital Relays. IEEE Transaction on Power Delivery. 25:2789–2796, 810

Keyhani, A. 2011. Smart Power Grid Renewable Energy Systems. Wiley, Hoboken

Rikos, E., S. Tselepis and A. Neris. 2008. Stability in Minigrids with Large PV Penetration under Weather Disturbances – Implementation to the Power System of Kythnos. In the Proceedings of European PV-Hybrid and Minigrid Conference

Ajewole, T.O., P.R.M. Craven, O. Kayode and O.S. Babalola. 2018. Simulation of Load-Sharing in Standalone Distributed Generation System. In the Proceedings of International Conference on Clean and Green Energy,

Magdy, G., E.A. Mohamed, G. Shabib, A.A. Elbaset, and Y. Mitani. 2018. Microgrid Dynamic Security Considering High Penetration of Renewable Energy. Protection and Control of Modern Power Systems. 3, /10.1186/s41601-018-0093-1

Zamani, M.A., T.S. Sidhu and A.A. Yazdani. A Protection Strategy and Microprocessor-Based Relay for Low-Voltage Microgrids. IEEE Transaction on Power Delivery. 26:1873–1883, WRD. 2011.2120628

Singh, A. and G.A. Sathans. 2016. Optimized PID Controller for Frequency Regulation in Standalone AC Microgrid. In the Proceedings of IEEE 7th India International Conference on Power Electronics

Teimourzadeh, S., F. Aminifar, M. Davarpanah and M. Shahidehpour. 2017. Adaptive Protection For Preserving Microgrid Security. IEEE Transaction on Smart Grid. 1:1– 9

Wang, Y., H.P. Painemal and K. Sun. 2017. Online Analysis of Voltage Security in a Microgrid Using Convolutional Neural Networks. IEEE Power and Energy Society General Meeting

Kerdphol, T., F.S. Rahman, Y. Mitani, M. Watanabe and S. Küfeoğlu. 2018. Robust Virtual Inertia Control of an Islanded Microgrid Considering High Penetration of Renewable Energy. IEEE Access. 6:625–636

Ajewole, T.O., M.O. Lawal, K.O. Alawode and M.O. Omoigui. 2019. Rotor Angle Dynamics in Multi-Machine Grid-Independent District Minigrid. In the Proceedings of International Conference on Engineering and Environmental Sciences, 776 – 784




How to Cite

Ajewole, T. O., Olabode, O., Akinyele, D., Amole, A. ., Fadipe, O., Olatunde Oladepo, & Hammed O. Lasisi. (2022). Security Study on Freestanding Minigrid with Multiple Rotary Energy Sources: Security Study on Minigrid. Journal of Energy and Safety Technology (JEST), 5(2). Retrieved from